Debiting a deceased person's account

I sent an email to *** informing Multichoice that my father passed away and that they should cancel his account with immediate effect. They acknowledged receiving my email and provided me with a reference number: ***3. I provided all the deceased's documentation to Multichoice to validate my request. I recently noticed that they are still debiting my late father's account when I checked his bank statement. I am really disappointed with the service I am getting from Multichoice.