Warning: assert(): Cannot load the "file" entity with NULL ID. failed in Drupal\Core\Entity\EntityStorageBase->load() (line 249 of core/lib/Drupal/Core/Entity/EntityStorageBase.php).
Warning: array_flip(): Can only flip STRING and INTEGER values! in Drupal\Core\Entity\EntityStorageBase->loadMultiple() (line 266 of core/lib/Drupal/Core/Entity/EntityStorageBase.php).
Notice: Undefined variable: fileUrl in Drupal\armonea_matchmaker\Form\MatchmakerConfig->buildForm() (line 228 of modules/custom/armonea_matchmaker/src/Form/MatchmakerConfig.php).