diff --git a/app/assets/javascripts/app/controllers/agent_ticket_create/sidebar_customer.coffee b/app/assets/javascripts/app/controllers/agent_ticket_create/sidebar_customer.coffee
index cbfd4e7e9..b4b80bdeb 100644
--- a/app/assets/javascripts/app/controllers/agent_ticket_create/sidebar_customer.coffee
+++ b/app/assets/javascripts/app/controllers/agent_ticket_create/sidebar_customer.coffee
@@ -1,7 +1,7 @@
 class SidebarCustomer extends App.Controller
   sidebarItem: =>
     return if !@permissionCheck('ticket.agent')
-    return if !@params.customer_id
+    return if _.isEmpty(@params.customer_id)
     {
       head:    'Customer'
       name:    'customer'
@@ -18,6 +18,7 @@ class SidebarCustomer extends App.Controller
 
   showCustomer: (el) =>
     @el = el
+    return if _.isEmpty(@params.customer_id)
     new App.WidgetUser(
       el:       @el
       user_id:  @params.customer_id
diff --git a/app/assets/javascripts/app/controllers/ticket_customer.coffee b/app/assets/javascripts/app/controllers/ticket_customer.coffee
index edb5df0c0..ba50eb0ba 100644
--- a/app/assets/javascripts/app/controllers/ticket_customer.coffee
+++ b/app/assets/javascripts/app/controllers/ticket_customer.coffee
@@ -18,8 +18,19 @@ class App.TicketCustomer extends App.ControllerModal
   onSubmit: (e) =>
     params = @formParam(e.target)
 
-    @customer_id = params['customer_id']
+    ticket = App.Ticket.find(@ticket_id)
+    ticket.customer_id = params['customer_id']
+    errors = ticket.validate()
 
+    if !_.isEmpty(errors)
+      @log 'error', errors
+      @formValidate(
+        form:   e.target
+        errors: errors
+      )
+      return
+
+    @customer_id = params['customer_id']
     callback = =>
 
       # close modal
diff --git a/app/assets/javascripts/app/lib/app_post/_object_organization_autocompletion.coffee b/app/assets/javascripts/app/lib/app_post/_object_organization_autocompletion.coffee
index 011dc2202..da0d8b2ee 100644
--- a/app/assets/javascripts/app/lib/app_post/_object_organization_autocompletion.coffee
+++ b/app/assets/javascripts/app/lib/app_post/_object_organization_autocompletion.coffee
@@ -71,7 +71,7 @@ class App.ObjectOrganizationAutocompletion extends App.Controller
     @open()
 
   focusInput: =>
-    @objectSelect.focus() if not @formControl.hasClass 'focus'
+    @objectSelect.focus() if not @formControl.hasClass('focus')
 
   onBlur: =>
     selectObject = @objectSelect.val()
@@ -85,6 +85,9 @@ class App.ObjectOrganizationAutocompletion extends App.Controller
           @objectId.val("guess:#{selectObject}")
     @formControl.removeClass 'focus'
 
+  resetObjectSelection: =>
+    @objectId.val('').trigger('change')
+
   onObjectClick: (e) =>
     objectId = $(e.currentTarget).data('object-id')
     @selectObject(objectId)
@@ -103,23 +106,23 @@ class App.ObjectOrganizationAutocompletion extends App.Controller
     # Only work with the last one since its the newest one
     objectId = @objectId.val().split(',').pop()
 
-    return if !objectId
-    return if !App[@objectSingle].exists(objectId)
-    object = App[@objectSingle].find(objectId)
-    name = object.displayName()
+    if objectId && App[@objectSingle].exists(objectId)
+      object = App[@objectSingle].find(objectId)
+      name = object.displayName()
 
-    if @attribute.multiple
-      # create token
-      @createToken name, objectId
-    else
-      if object.email
+      if @attribute.multiple
 
-        # quote name for special character
-        if name.match(/\@|,|;|\^|\+|#|§|\$|%|&|\/|\(|\)|=|\?|!|\*|\[|\]/)
-          name = "\"#{name}\""
-        name += " <#{object.email}>"
+        # create token
+        @createToken(name, objectId)
+      else
+        if object.email
 
-      @objectSelect.val(name)
+          # quote name for special character
+          if name.match(/\@|,|;|\^|\+|#|§|\$|%|&|\/|\(|\)|=|\?|!|\*|\[|\]/)
+            name = "\"#{name}\""
+          name += " <#{object.email}>"
+
+        @objectSelect.val(name)
 
     if @callback
       @callback(objectId)
@@ -321,12 +324,16 @@ class App.ObjectOrganizationAutocompletion extends App.Controller
     @hideOrganizationMembers()
 
     # hide dropdown
-    if !query
+    if _.isEmpty(query)
       @emptyResultList()
 
       if !@attribute.disableCreateObject
         @recipientList.append(@buildObjectNew())
 
+      # reset object selection
+      @resetObjectSelection()
+      return
+
     # show dropdown
     if query && ( !@attribute.minLengt || @attribute.minLengt <= query.length )
       @lazySearch(query)
diff --git a/script/build/test_slice_tests.sh b/script/build/test_slice_tests.sh
index 34e837538..559f49fa0 100755
--- a/script/build/test_slice_tests.sh
+++ b/script/build/test_slice_tests.sh
@@ -20,6 +20,7 @@ if [ "$LEVEL" == '1' ]; then
   rm test/browser/admin_role_test.rb
   # test/browser/agent_navigation_and_title_test.rb
   rm test/browser/agent_ticket_attachment_test.rb
+  rm test/browser/agent_ticket_create_reset_customer_selection_test.rb
   rm test/browser/agent_ticket_email_reply_keep_body_test.rb
   rm test/browser/agent_ticket_email_signature_test.rb
   rm test/browser/agent_ticket_link_test.rb
@@ -78,6 +79,7 @@ elif [ "$LEVEL" == '2' ]; then
   rm test/browser/agent_navigation_and_title_test.rb
   rm test/browser/agent_organization_profile_test.rb
   rm test/browser/agent_ticket_attachment_test.rb
+  rm test/browser/agent_ticket_create_reset_customer_selection_test.rb
   rm test/browser/agent_ticket_email_reply_keep_body_test.rb
   rm test/browser/agent_ticket_email_signature_test.rb
   rm test/browser/agent_ticket_link_test.rb
@@ -136,6 +138,7 @@ elif [ "$LEVEL" == '3' ]; then
   rm test/browser/agent_navigation_and_title_test.rb
   rm test/browser/agent_organization_profile_test.rb
   # test/browser/agent_ticket_attachment_test.rb
+  # test/browser/agent_ticket_create_reset_customer_selection_test.rb
   # test/browser/agent_ticket_email_reply_keep_body_test.rb
   # test/browser/agent_ticket_email_signature_test.rb
   # test/browser/agent_ticket_link_test.rb
@@ -194,6 +197,7 @@ elif [ "$LEVEL" == '4' ]; then
   rm test/browser/agent_navigation_and_title_test.rb
   rm test/browser/agent_organization_profile_test.rb
   rm test/browser/agent_ticket_attachment_test.rb
+  rm test/browser/agent_ticket_create_reset_customer_selection_test.rb
   rm test/browser/agent_ticket_email_reply_keep_body_test.rb
   rm test/browser/agent_ticket_email_signature_test.rb
   rm test/browser/agent_ticket_link_test.rb
@@ -251,6 +255,7 @@ elif [ "$LEVEL" == '5' ]; then
   rm test/browser/agent_navigation_and_title_test.rb
   # test/browser/agent_organization_profile_test.rb
   rm test/browser/agent_ticket_attachment_test.rb
+  rm test/browser/agent_ticket_create_reset_customer_selection_test.rb
   rm test/browser/agent_ticket_email_reply_keep_body_test.rb
   rm test/browser/agent_ticket_email_signature_test.rb
   rm test/browser/agent_ticket_link_test.rb
@@ -311,6 +316,7 @@ elif [ "$LEVEL" == '6' ]; then
   rm test/browser/agent_navigation_and_title_test.rb
   rm test/browser/agent_organization_profile_test.rb
   rm test/browser/agent_ticket_attachment_test.rb
+  rm test/browser/agent_ticket_create_reset_customer_selection_test.rb
   rm test/browser/agent_ticket_email_reply_keep_body_test.rb
   rm test/browser/agent_ticket_email_signature_test.rb
   rm test/browser/agent_ticket_link_test.rb
diff --git a/test/browser/agent_ticket_create_reset_customer_selection_test.rb b/test/browser/agent_ticket_create_reset_customer_selection_test.rb
new file mode 100644
index 000000000..29ebe49dc
--- /dev/null
+++ b/test/browser/agent_ticket_create_reset_customer_selection_test.rb
@@ -0,0 +1,244 @@
+
+require 'browser_test_helper'
+
+class AgentTicketCreateResetCustomerSelectionTest < TestCase
+  def test_clear_customer
+    @browser = browser_instance
+    login(
+      username: 'master@example.com',
+      password: 'test',
+      url: browser_url,
+    )
+    tasks_close_all()
+
+    click(css: 'a[href="#new"]')
+    click(css: 'a[href="#ticket/create"]')
+    sleep 2
+
+    exists(css: '.content.active .newTicket')
+    exists(css: '.content.active .tabsSidebar .sidebar[data-tab="template"]')
+    exists(css: '.content.active .tabsSidebar .tabsSidebar-tab.active[data-tab="template"]')
+
+    exists_not(css: '.content.active .tabsSidebar .sidebar[data-tab="customer"]')
+    exists_not(css: '.content.active .tabsSidebar .tabsSidebar-tab[data-tab="customer"]')
+
+    click(css: '.content.active .newTicket [name="customer_id_completion"]')
+
+    # check if pulldown is open, it's not working stable via selenium
+    @browser.execute_script( "$('.content.active .newTicket .js-recipientDropdown').addClass('open')" )
+
+    set(
+      css: '.content.active .newTicket input[name="customer_id_completion"]',
+      value: 'nicole',
+    )
+
+    sleep 2
+    sendkey(value: :enter)
+    sleep 1
+
+    exists(css: '.content.active .newTicket')
+    exists(css: '.content.active .tabsSidebar .sidebar[data-tab="template"]')
+    exists(css: '.content.active .tabsSidebar .tabsSidebar-tab.active[data-tab="template"]')
+
+    exists(css: '.content.active .tabsSidebar .sidebar[data-tab="customer"]')
+    exists(css: '.content.active .tabsSidebar .tabsSidebar-tab[data-tab="customer"]')
+
+    set(
+      css: '.content.active .newTicket input[name="customer_id_completion"]',
+      value: '',
+    )
+    sendkey(value: :backspace)
+
+    sleep 1
+
+    exists(css: '.content.active .newTicket')
+    exists(css: '.content.active .tabsSidebar .sidebar[data-tab="template"]')
+    exists(css: '.content.active .tabsSidebar .tabsSidebar-tab.active[data-tab="template"]')
+
+    exists_not(css: '.content.active .tabsSidebar .sidebar[data-tab="customer"]')
+    exists_not(css: '.content.active .tabsSidebar .tabsSidebar-tab[data-tab="customer"]')
+
+    set(
+      css: '.content.active .newTicket input[name="title"]',
+      value: 'some title',
+    )
+
+    set(
+      css: '.content.active .newTicket div[data-name="body"]',
+      value: 'some body',
+    )
+
+    select(
+      css: '.content.active .newTicket select[name="group_id"]',
+      value: 'Users',
+    )
+
+    click(css: '.content.active .newTicket .js-submit')
+
+    watch_for(
+      css: '.content.active .newTicket .user_autocompletion.form-group.has-error',
+    )
+
+    # cleanup
+    tasks_close_all()
+  end
+
+  def test_clear_customer_use_email
+    @browser = browser_instance
+    login(
+      username: 'master@example.com',
+      password: 'test',
+      url: browser_url,
+    )
+    tasks_close_all()
+
+    click(css: 'a[href="#new"]')
+    click(css: 'a[href="#ticket/create"]')
+    sleep 2
+
+    exists(css: '.content.active .newTicket')
+    exists(css: '.content.active .tabsSidebar .sidebar[data-tab="template"]')
+    exists(css: '.content.active .tabsSidebar .tabsSidebar-tab.active[data-tab="template"]')
+
+    exists_not(css: '.content.active .tabsSidebar .sidebar[data-tab="customer"]')
+    exists_not(css: '.content.active .tabsSidebar .tabsSidebar-tab[data-tab="customer"]')
+
+    click(css: '.content.active .newTicket [name="customer_id_completion"]')
+
+    # check if pulldown is open, it's not working stable via selenium
+    @browser.execute_script( "$('.content.active .newTicket .js-recipientDropdown').addClass('open')" )
+
+    set(
+      css: '.content.active .newTicket input[name="customer_id_completion"]',
+      value: 'nicole',
+    )
+
+    sleep 2
+    sendkey(value: :enter)
+    sleep 1
+
+    exists(css: '.content.active .newTicket')
+    exists(css: '.content.active .tabsSidebar .sidebar[data-tab="template"]')
+    exists(css: '.content.active .tabsSidebar .tabsSidebar-tab.active[data-tab="template"]')
+
+    exists(css: '.content.active .tabsSidebar .sidebar[data-tab="customer"]')
+    exists(css: '.content.active .tabsSidebar .tabsSidebar-tab[data-tab="customer"]')
+
+    set(
+      css: '.content.active .newTicket input[name="customer_id_completion"]',
+      value: '',
+    )
+    sendkey(value: :backspace)
+
+    sleep 1
+
+    exists(css: '.content.active .newTicket')
+    exists(css: '.content.active .tabsSidebar .sidebar[data-tab="template"]')
+    exists(css: '.content.active .tabsSidebar .tabsSidebar-tab.active[data-tab="template"]')
+
+    exists_not(css: '.content.active .tabsSidebar .sidebar[data-tab="customer"]')
+    exists_not(css: '.content.active .tabsSidebar .tabsSidebar-tab[data-tab="customer"]')
+
+    set(
+      css: '.content.active .newTicket input[name="customer_id_completion"]',
+      value: 'somecustomer_not_existing_right_now@example.com',
+    )
+
+    set(
+      css: '.content.active .newTicket input[name="title"]',
+      value: 'some title',
+    )
+
+    set(
+      css: '.content.active .newTicket div[data-name="body"]',
+      value: 'some body',
+    )
+
+    select(
+      css: '.content.active .newTicket select[name="group_id"]',
+      value: 'Users',
+    )
+
+    click(css: '.content.active .newTicket .js-submit')
+
+    watch_for(
+      css: '.content.active .ticketZoom-header .ticket-number',
+      value: '\d',
+    )
+
+    click(css: '.content.active .tabsSidebar-tabs .tabsSidebar-tab[data-tab="customer"]')
+
+    match(
+      css: '.content.active .tabsSidebar .sidebar[data-tab="customer"]',
+      value: 'somecustomer_not_existing_right_now@example.com',
+    )
+
+    click(css: '.content.active .tabsSidebar .sidebar[data-tab="customer"] .js-actions')
+    click(css: '.content.active .tabsSidebar .sidebar[data-tab="customer"] .js-actions li[data-type="customer-change"]')
+
+    watch_for(
+      css: '.content.active .modal',
+    )
+
+    exists_not(
+      css: '.content.active .modal .user_autocompletion.form-group.has-error',
+    )
+
+    click(css: '.content.active .modal .js-submit')
+
+    watch_for(
+      css: '.content.active .modal .user_autocompletion.form-group.has-error',
+    )
+
+    set(
+      css: '.content.active .modal input[name="customer_id_completion"]',
+      value: 'master',
+    )
+
+    click(css: '.content.active .modal .js-submit')
+
+    watch_for(
+      css: '.content.active .modal .user_autocompletion.form-group.has-error',
+    )
+
+    set(
+      css: '.content.active .modal input[name="customer_id_completion"]',
+      value: 'master',
+    )
+
+    sendkey(value: :enter)
+    sleep 1
+
+    set(
+      css: '.content.active .modal input[name="customer_id_completion"]',
+      value: '',
+    )
+    sendkey(value: :backspace)
+    sleep 1
+
+    click(css: '.content.active .modal .js-submit')
+
+    watch_for(
+      css: '.content.active .modal .user_autocompletion.form-group.has-error',
+    )
+
+    set(
+      css: '.content.active .modal input[name="customer_id_completion"]',
+      value: 'master',
+    )
+
+    sendkey(value: :enter)
+    sleep 1
+
+    click(css: '.content.active .modal .js-submit')
+    #click(css: '.content.active .tabsSidebar-tabs .tabsSidebar-tab[data-tab="customer"]')
+
+    watch_for(
+      css: '.content.active .tabsSidebar .sidebar[data-tab="customer"]',
+      value: 'master@example.com',
+    )
+
+    # cleanup
+    tasks_close_all()
+  end
+end
diff --git a/test/browser/agent_user_manage_test.rb b/test/browser/agent_user_manage_test.rb
index 4d2160f29..4c82d1b16 100644
--- a/test/browser/agent_user_manage_test.rb
+++ b/test/browser/agent_user_manage_test.rb
@@ -19,17 +19,17 @@ class AgentUserManageTest < TestCase
     sleep 1
 
     # create customer
-    click( css: 'a[href="#new"]' )
-    click( css: 'a[href="#ticket/create"]' )
-    click( css: '.active .newTicket [name="customer_id_completion"]' )
+    click(css: 'a[href="#new"]')
+    click(css: 'a[href="#ticket/create"]')
+    click(css: '.active .newTicket [name="customer_id_completion"]')
 
     # check if pulldown is open, it's not working stable via selenium
     @browser.execute_script( "$('.active .newTicket .js-recipientDropdown').addClass('open')" )
 
     sleep 1
-    sendkey( value: :arrow_down )
+    sendkey(value: :arrow_down)
     sleep 0.5
-    click( css: '.active .newTicket .recipientList-entry.js-objectNew' )
+    click(css: '.active .newTicket .recipientList-entry.js-objectNew')
     sleep 1
 
     set(
@@ -45,7 +45,7 @@ class AgentUserManageTest < TestCase
       value: customer_user_email,
     )
 
-    click( css: '.modal button.js-submit' )
+    click(css: '.modal button.js-submit')
     sleep 4
 
     # check is used to check selected
@@ -75,8 +75,8 @@ class AgentUserManageTest < TestCase
     # call new ticket screen again
     tasks_close_all()
 
-    click( css: 'a[href="#new"]' )
-    click( css: 'a[href="#ticket/create"]' )
+    click(css: 'a[href="#new"]')
+    click(css: 'a[href="#ticket/create"]')
     sleep 2
 
     match(
@@ -93,7 +93,7 @@ class AgentUserManageTest < TestCase
     )
     sleep 3
 
-    click( css: '.active .newTicket .recipientList-entry.js-object.is-active' )
+    click(css: '.active .newTicket .recipientList-entry.js-object.is-active')
     sleep 1
 
     # check is used to check selected
diff --git a/test/browser_test_helper.rb b/test/browser_test_helper.rb
index 909503218..3f4decb00 100644
--- a/test/browser_test_helper.rb
+++ b/test/browser_test_helper.rb
@@ -1261,7 +1261,7 @@ set type of task (closeTab, closeNextInOverview, stayOnTab)
             sleep 0.5
             return true
 
-          # match pn attribute
+          # match an attribute
           else
             text = if params[:attribute]
                      element.attribute(params[:attribute])