I have a weird issue with Models and their eloquent relations. The thing is that I have 2 Models , User and Subject. They are linked through belongsToMany relation like so :

class User extends Model {
    public function allowed_subjects()
      {
           return $this->belongsToMany(Subject::class);
      }
 }

and :

 class Subject extends Model { 
     public function users()
       {
         return $this->belongsToMany(User::class);
       } 
   }

the pivot table is named to convention "subject_user" and has "user_id" and "subject_id" fields. I defined a function in User class to check if the user has a certain subject like so :

public function hasSubject($subject='') {
$match = false;
if(is_string($subject)){
    if(!empty($this->allowed_subjects)
                    {
                   return $this->allowed_subjects->contains('name',$subject)? true : false;
                    }
            return false;
        }
       elseif(is_integer($subject))
       {
             if(!empty($this->allowed_subjects)
                 {
                     return $this->allowed_subjects->contains('id',$subject)? true : false;
                 }
             return false;
         }
      elseif(is_array($subject))
       {
           foreach($subject as $sbj)
             {
               if(is_integer($sbj))
                 {
                   $this->allowed_subjects->contains('id',$sbj)? $match = true : null;
                 }
               elseif(is_string($sbj))
               {
                   $this->allowed_subjects->contains('name',$sbj)? $match = true : null;
               }
              else{
                  continue;
             }
         }
        }
return $match;
   }

The function is working fine locally , but once I hosted the app in a DO server , It acts so weird , that hasSubject always returns false even if the user has the subject . So I run its tests and they return all green . I defined a route to test this function live like so :

Route::get('/hasSubject', function(){
       $cuser = \Auth::user();
       //foreach($cuser->allowed_subjects as $sbj){
           //echo $sbj->id." ".$sbj->name."<br>";
       //}
       echo "<hr>";
       dd($cuser->hasSubject(1));
     });

and then the magic happens , if I uncomment the foreach loop , it returns true (which is correct), but when it's commented , it return false and this is the case in all my controllers , if I print allowed_subjects before calling hasSubject it works fine , otherwise no . I am really losing my mind