Ver: 3.4.17 Update – Saved Fields is not working

Dear support, I have update to v3.4.17. However the Saved Fields is not working.

After you saved, it is not appearing under saved fields or anywhere!

Please see this Apache error whenever entering to edit the forms.

mod_fcgid: stderr: PHP Warning: Invalid argument supplied for foreach() in /var/www/vhosts/…./…./wp-content/plugins/ninja-forms/includes/Abstracts/ModelFactory.php on line 252, referer: https://……/wp-admin/admin.php?page=ninja-forms

Below the script that causing the error :
?
“foreach( $form_cache[ ‘fields’ ] as $cached_field ){
$field = new NF_Database_Models_Field( $this->_db, $cached_field[ ‘id’ ], $form_id );
$field->update_settings( $cached_field[ ‘settings’ ] );
$this->_fields[$field->get_id()] = $field;
$field_by_key[ $field->get_setting( ‘key’ ) ] = $field;
}
}”

Please look into it.

Thanks.