Is the resignation letter to the head of the department or to the personnel department?

The resignation letter of working in a hotel should be handed over to the personnel department, because it is the hotel, not the department, that wants to resign, and it should directly face the unit.

And shall comply with the provisions of Article 37 of the Labor Contract Law. "The employee may terminate the labor contract by notifying the employer in writing thirty days in advance. The employee may terminate the labor contract by notifying the employer three days in advance during the probation period.

Of course, we must keep the evidence or proof of submitting the resignation letter to the personnel department to avoid unnecessary disputes because we did not see the malicious lies in the resignation letter.