laravel must return a relationship instance

hasOne relation error laravel

//this is example how to return a relationship instance in laravel if u have some logic to get it or troubles

public function user()
    {
    $id = ///some code to get $id
        return $this->hasOne(User::class, 'id', 'id') // this just for new hasOne instance
            ->orWhere('id', $id); //get your niddle instanse
    }