Fatal error: Uncaught Error: Class "Illuminate\Database\Eloquent\Relations\Relation" not found in E:\www\gsp_smart\webman\vendor\illuminate\database\Eloquent\Relations\BelongsToMany.php:17 Stack trace: #0 {main} thrown in E:\www\gsp_smart\webman\vendor\illuminate\database\Eloquent\Relations\BelongsToMany.php on line 17