Fatal error: Uncaught Error: Class "Illuminate\Database\Eloquent\Relations\BelongsTo" not found in /opt/lampp/htdocs/forum/flarum/vendor/illuminate/database/Eloquent/Relations/MorphTo.php:11 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/forum/flarum/vendor/illuminate/database/Eloquent/Relations/MorphTo.php on line 11