Trying to cancel a deceased person's contract

My father passed away and I am trying to cancel his cellphone contract. In the email they promise to resolve the issue within 5 working days, it has now been 10 working days with NO feedback. The phone number provided also does not work!!!! It has also taken me 45 minutes where I was sent from one department to another, without anyone knowing what to do.<br> <br> This is unacceptable!!