The Message Private module provides a message type and associated entity reference fields, enabling sending and receiving private messages using The Message Stack.
The website encountered an unexpected error. Please try again later.</br></br><em class="placeholder">Drupal\Core\Entity\EntityStorageException</em>: Unable to get a value with a non-numeric delta in a list. in <em class="placeholder">Drupal\Core\Entity\Sql\SqlContentEntityStorage->save()</em> (line <em class="placeholder">783</em> of <em class="placeholder">core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php</em>). <pre class="backtrace">message_private_message_insert(Object)
call_user_func_array('message_private_message_insert', Array) (Line: 403)
Drupal\Core\Extension\ModuleHandler->invokeAll('message_insert', Array) (Line: 204)
Drupal\Core\Entity\EntityStorageBase->invokeHook('insert', Object) (Line: 756)
Drupal\Core\Entity\ContentEntityStorageBase->invokeHook('insert', Object) (Line: 507)
Drupal\Core\Entity\EntityStorageBase->doPostSave(Object, ) (Line: 641)
Drupal\Core\Entity\ContentEntityStorageBase->doPostSave(Object, ) (Line: 432)
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Fixes #18
When saving the private message I'm getting: