Kenapa komentar di satu forum berlaku di forum lainnya (Laravel 5.4)

Saya buat sistem komentar, tapi ketika saya komentar di forum 1, di forum yang ke 2 juga ada komentar saya yang sama di forum 1.. Apa salahnya di bagian Model,Table, atau saya pada saat looping nya salah.. Terima kasih. Bagian Model User:

class Forum extends Model
{
  public function user() {

     return $this->belongsTo('App\Models\User');

    }

  public function tags() {

    return $this->belongsToMany('App\Models\Tag');

    }

    public function comment() {

      return $this->belongsTo('App\Models\Comment');

      }

}

ForumController

    public function show($id)
    {
      $user    = User::first();
      $forum   = Forum::where('slug', $id)->first();
      $tags    = Tag::all();
      $comment = Comment::paginate(3);

      $tags2  = array();
      foreach ($tags as $tag) {
        $tags2[$tag->id] = $tag->name;
      }
      return view('forum/show')->withForum($forum)->withTags($tags2)->withUser($user)->withComments($comment);
    }

Bagian Model Comment

class Comment extends Model
{
  public function user() {

     return $this->belongsTo('App\Models\User');

    }

  public function forum() {

    return $this->belongsTo('App\Models\Forum');

    }

}

show.blade.php

     <div class="row">
       <div class="col m12">

         <div class="comment">
           <ul class="collection with-header">

             <li class="collection-header"> <h4> Komentar </h4> </li>
             <li class="collection-item avatar">
               @foreach ($comments as $comment)
                 <img src="{{ asset('storage/images/levi.gif')}}" class="left circle">
                 <span id="user" class="left">  {{ $comment->user->name }} </span>
                 <p> {{ $comment->comment }} </p>
               @endforeach

                  {{ $comments->links() }}

             @if(!Auth::guest())
               <form action="/comment/{{ $forum->id }}"id="comment-textarea" method="post">
                 <textarea name="comment"> </textarea>
                 <input id="btn-comment" type="submit" name="submit" value="Tulis komentar...">
                 {{ csrf_field() }}
               </form>
             @else

              <li class="collection-item avatar">Jika ingin berkomentar, <br> silahkan <a id="login_btn" href="/login">login</a> terlebih dahulu.</li>

              @endif
             </li>

           </ul>
          </div>