ERROR by checkout: _editor_get_file_uuids_by_field()

i have an error after checkout...i don't know what it is ;(
do you have an solution?
thank's in advance!

working on localhost: drupal 8.1.2, php 7

The website encountered an unexpected error. Please try again later.
TypeError: Argument 1 passed to _editor_get_file_uuids_by_field() must implement interface Drupal\Core\Entity\EntityInterface, null given, called in /Users/joerg/Sites/dev/alpha2/core/modules/editor/editor.module on line 367 in _editor_get_file_uuids_by_field() (line 465 of core/modules/editor/editor.module).
_editor_get_file_uuids_by_field(NULL) (Line: 367)
editor_entity_update(Object)
call_user_func_array('editor_entity_update', Array) (Line: 402)
Drupal\Core\Extension\ModuleHandler->invokeAll('entity_update', Array) (Line: 169)
Drupal\Core\Entity\EntityStorageBase->invokeHook('update', Object) (Line: 418)
Drupal\Core\Entity\ContentEntityStorageBase->invokeHook('update', Object) (Line: 470)
Drupal\Core\Entity\EntityStorageBase->doPostSave(Object, 1) (Line: 304)
Drupal\Core\Entity\ContentEntityStorageBase->doPostSave(Object, 1) (Line: 395)
Drupal\Core\Entity\EntityStorageBase->save(Object) (Line: 747)
Drupal\Core\Entity\Sql\SqlContentEntityStorage->save(Object) (Line: 358)
Drupal\Core\Entity\Entity->save() (Line: 177)
uc_payment_uc_payment_receipt_insert(Object)
call_user_func_array('uc_payment_uc_payment_receipt_insert', Array) (Line: 402)
Drupal\Core\Extension\ModuleHandler->invokeAll('uc_payment_receipt_insert', Array) (Line: 167)
Drupal\Core\Entity\EntityStorageBase->invokeHook('insert', Object) (Line: 418)
Drupal\Core\Entity\ContentEntityStorageBase->invokeHook('insert', Object) (Line: 470)
Drupal\Core\Entity\EntityStorageBase->doPostSave(Object, ) (Line: 304)
Drupal\Core\Entity\ContentEntityStorageBase->doPostSave(Object, ) (Line: 395)
Drupal\Core\Entity\EntityStorageBase->save(Object) (Line: 747)
Drupal\Core\Entity\Sql\SqlContentEntityStorage->save(Object) (Line: 358)
Drupal\Core\Entity\Entity->save() (Line: 157)
uc_payment_enter('11', 'free_order', 0, 0, NULL, Object) (Line: 37)
Drupal\uc_payment\Plugin\Ubercart\PaymentMethod\FreeOrder->orderSubmit(Object) (Line: 97)
uc_payment_checkout_review_form_validate(Array, Object)
call_user_func_array('uc_payment_checkout_review_form_validate', Array) (Line: 83)
Drupal\Core\Form\FormValidator->executeValidateHandlers(Array, Object) (Line: 270)
Drupal\Core\Form\FormValidator->doValidateForm(Array, Object, 'uc_cart_checkout_review_form') (Line: 119)
Drupal\Core\Form\FormValidator->validateForm('uc_cart_checkout_review_form', Array, Object) (Line: 569)
Drupal\Core\Form\FormBuilder->processForm('uc_cart_checkout_review_form', Array, Object) (Line: 314)
Drupal\Core\Form\FormBuilder->buildForm('uc_cart_checkout_review_form', Object) (Line: 212)
Drupal\Core\Form\FormBuilder->getForm('Drupal\uc_cart\Form\CheckoutReviewForm', Object) (Line: 214)
Drupal\uc_cart\Controller\CheckoutController->review()
call_user_func_array(Array, Array) (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 574)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array) (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
call_user_func_array(Object, Array) (Line: 139)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 62)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 57)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 47)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 98)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 77)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 47)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 50)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 628)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)