Saving Paragraph: Column 'langcode' cannot be null

Seeing this as I'm attempting to save a paragraph:

An AJAX HTTP error occurred.
HTTP Result Code: 500
Debugging information follows.
Path: /batch?id=5827&op=do_nojs&op=do
StatusText: 500 Service unavailable (with message)
ResponseText: The website encountered an unexpected error. Please try again later.Drupal\Core\Entity\EntityStorageException: SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'langcode' cannot be null: INSERT INTO {paragraphs_item} (revision_id, type, uuid, langcode) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3); Array
(
[:db_insert_placeholder_0] => 
[:db_insert_placeholder_1] => product_dimensions
[:db_insert_placeholder_2] => 140ebf13-6a17-4054-8801-7281ec194706
[:db_insert_placeholder_3] => 
)
in Drupal\Core\Entity\Sql\SqlContentEntityStorage->save() (line 783 of core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php). Drupal\Core\Database\Statement->execute(Array, Array) (Line: 625)
Drupal\Core\Database\Connection->query('INSERT INTO {paragraphs_item} (revision_id, type, uuid, langcode) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3)', Array, Array) (Line: 358)
Drupal\Core\Database\Driver\mysql\Connection->query('INSERT INTO {paragraphs_item} (revision_id, type, uuid, langcode) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3)', Array, Array) (Line: 32)
Drupal\Core\Database\Driver\mysql\Insert->execute() (Line: 863)
Drupal\Core\Entity\Sql\SqlContentEntityStorage->doSaveFieldItems(Object) (Line: 578)
Drupal\Core\Entity\ContentEntityStorageBase->doSave(NULL, Object) (Line: 429)
Drupal\Core\Entity\EntityStorageBase->save(Object) (Line: 774)
Drupal\Core\Entity\Sql\SqlContentEntityStorage->save(Object) (Line: 390)
Drupal\Core\Entity\Entity->save() (Line: 260)
Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem->preSave() (Line: 256)
Drupal\entity_reference_revisions\Plugin\Field\FieldType\EntityReferenceRevisionsItem->preSave() (Line: 233)
Drupal\Core\Field\FieldItemList->delegateMethod('preSave') (Line: 191)
Drupal\Core\Field\FieldItemList->preSave() (Line: 794)
Drupal\Core\Entity\ContentEntityStorageBase->invokeFieldMethod('preSave', Object) (Line: 744)
Drupal\Core\Entity\ContentEntityStorageBase->invokeHook('presave', Object) (Line: 472)
Drupal\Core\Entity\EntityStorageBase->doPreSave(Object) (Line: 613)
Drupal\Core\Entity\ContentEntityStorageBase->doPreSave(Object) (Line: 426)
Drupal\Core\Entity\EntityStorageBase->save(Object) (Line: 774)
Drupal\Core\Entity\Sql\SqlContentEntityStorage->save(Object) (Line: 390)
Drupal\Core\Entity\Entity->save() (Line: 562)
Drupal\views_bulk_edit\Plugin\Action\ModifyEntityValues->execute(Object) (Line: 66)
Drupal\views_bulk_operations\Action\ViewsBulkOperationsActionBase->executeMultiple(Array) (Line: 372)
Drupal\views_bulk_operations\Service\ViewsBulkOperationsActionProcessor->process() (Line: 126)
Drupal\views_bulk_operations\ViewsBulkOperationsBatch::operation(Array, Array) (Line: 294)
... etc etc...

Looks like a langcode isn't being set as the new paragraph is created.