Method [getRedirectUrl] does not exist

Hi after upgrading my project from Laravel 5.4 to 5.5 i get this error on submit which worked fine on 5.4

This is the code where i get the error.

use Illuminate\Http\Request;

...
....

public function putComment(Request $request)
{
    $comment = $request->user()->comments()->create([
        'approved' => 0,
        'media_id' => $request->input('media_id'),
        'body'     => $request->input('body'),
    ]);

    .....
    ......
    .......

    return redirect($this->getRedirectUrl() . '#comment-' . $comment->id);
}

Any help would be very much appreciated.

Thank you.

via Chebli Mohamed