Error: Call to a member function getFileUri() on null in Drupal\doc_serialization\Encoder\Docx->encode() (line 71 of modules/doc_serialization/src/Encoder/Docx.php).

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The website encountered an unexpected error. Please try again later.
Error: Call to a member function getFileUri() on null in Drupal\doc_serialization\Encoder\Docx->encode() (line 71 of modules/doc_serialization/src/Encoder/Docx.php).

Drupal\doc_serialization\Encoder\Docx->encode(Array, 'docx', Array) (Line: 40)
Symfony\Component\Serializer\Encoder\ChainEncoder->encode(Array, 'docx', Array) (Line: 272)
Symfony\Component\Serializer\Serializer->encode(Array, 'docx', Array) (Line: 119)
Symfony\Component\Serializer\Serializer->serialize(Array, 'docx', Array) (Line: 142)
Drupal\rest\Plugin\views\style\Serializer->render() (Line: 450)
Drupal\rest\Plugin\views\display\RestExport->Drupal\rest\Plugin\views\display\{closure}() (Line: 582)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 451)
Drupal\rest\Plugin\views\display\RestExport->render() (Line: 76)
Drupal\doc_serialization\Plugin\views\display\WordExport->render() (Line: 1533)
Drupal\views\ViewExecutable->render() (Line: 441)
Drupal\rest\Plugin\views\display\RestExport->execute() (Line: 1630)
Drupal\views\ViewExecutable->executeDisplay('word_export_1', Array) (Line: 77)
Drupal\views\Element\View::preRenderViewElement(Array)
call_user_func(Array, Array) (Line: 378)
Drupal\Core\Render\Renderer->doRender(Array, 1) (Line: 195)
Drupal\Core\Render\Renderer->render(Array, 1) (Line: 139)
Drupal\Core\Render\Renderer->Drupal\Core\Render\{closure}() (Line: 582)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 140)
Drupal\Core\Render\Renderer->renderRoot(Array) (Line: 56)
Drupal\doc_serialization\Plugin\views\display\WordExport::buildResponse('teilnehmende_exportieren', 'word_export_1', Array) (Line: 52)
Drupal\views\Routing\ViewPageController->handle('teilnehmende_exportieren', 'word_export_1', Object)
call_user_func_array(Array, Array) (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 582)
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}() (Line: 151)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 68)
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: 99)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 78)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 47)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 52)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 669)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)