Database error: title required (or my lack of sleep ;))

I couldn't get this to work. Really looking forward to getting it working :-) Hopefully some pointers.

I activate the hiding of the title using this module, and hide it in form display options, however if I create some content with my content type, it gives an error in the Drupal logs, saying it needs the title field.

I get this error in the browser when trying to create some content of that content type: "The website encountered an unexpected error. Please try again later."

This shows in the logs as well:
Drupal\Core\Database\IntegrityConstraintViolationException: SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'title' cannot be null: INSERT INTO {node_field_data} (nid, vid, type, langcode, title, uid, status, created, changed, promote, sticky, revision_translation_affected, default_langcode) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6, :db_insert_placeholder_7, :db_insert_placeholder_8, :db_insert_placeholder_9, :db_insert_placeholder_10, :db_insert_placeholder_11, :db_insert_placeholder_12); Array ( [:db_insert_placeholder_0] => 18 [:db_insert_placeholder_1] => 26 [:db_insert_placeholder_2] => testimonial [:db_insert_placeholder_3] => en [:db_insert_placeholder_4] => [:db_insert_placeholder_5] => 1 [:db_insert_placeholder_6] => 1 [:db_insert_placeholder_7] => 1490221447 [:db_insert_placeholder_8] => 1490221451 [:db_insert_placeholder_9] => 1 [:db_insert_placeholder_10] => 0 [:db_insert_placeholder_11] => 1 [:db_insert_placeholder_12] => 1 ) in Drupal\Core\Database\Connection->handleQueryException() (line 668 of /Library/WebServer/Documents/bristol_local_lets/core/lib/Drupal/Core/Database/Connection.php).

Thanks! Looking forward to using this awesome module :-)

It could be down to my lack of sleep ;-)