500 Internal Server Error on Ajax request. Not sure the origin of the problem

$.ajax({
    method: 'POST',
    url: urlDeleteComment,
    data: {
        commentId: commentId,
        _method: 'DELETE',
        _token: token
    }
}).done(function(response) {

})

<form method='POST' id='delete_comment'>
    <input type="hidden" name="comment_id" value="{{ $comment->id }}">
    @csrf
    <div id="status" style="display: none;"></div>
    <button class='submit-btn delete-comment' type='submit' name='commentDelete'>X</button>
</form>

// POST 
Route::post('/comment/delete', 'CommentsController@deleteComment')->name('deleteComment');

<script type="text/javascript">  
$(document).ready(function(){

 $('#delete_comment').on('submit', function(event){
  event.preventDefault();
  // ADD WAIT CSS IF YOU WANT HERE :) 
  $.ajax({
   url:"{{ route('deleteComment') }}",
   method:"POST",
   data: new FormData(this),
   // DATA RETURN JSON
   dataType:'JSON',
   contentType: false,
   cache: false,
   processData: false,
   success:function(data)
   {
    // REMOVE YOUR WAIT CSS BEFORE SHOW YOUR SUCCESS MSG

    // SHOW SUCCESS OR WARNING MSG
    jQuery('#status').toggle('show');
    $('#status').addClass(data.status);
    $('#status').innerHTML = data.msg;
   },
   error: function(data) {
    console.log(data);
   }
   });
 });

});
</script>

<?php
protected function deleteComment(Request $request){
    // NOT GIVE ANY ONE TO DELETE YOUR COMMNET 
    $comment = Comment::find($request->comment_id);
    // CHECK IF IS COMMNET IN DATABASE :) 
    if ($comment) {
        $comment->delete();
        return response()->json([
            'msg' => 'success', 
            'status' => 'alert alert-success'
        ]);
    }
    return response()->json([
        'msg' => 'error, not found', 
        'status' => 'alert alert-danger'
    ]);
}

?>