Deceased account

Level 2
I've been trying for weeks to cancel my late Father's internet. Have called several times, have been assured this person and that person will deal with it and get back to me, never hear from anyone. I've emailed the death certificate to three different emails I've been given and my ID. I'm overseas and this is very stressful, I can't keep calling and being told it will be done or dealt with and it's not. Is the process to close an account usually this frustrating ? The customer is dead, pretty clear they don't need the service.