Supersonic refuse to cancel my account.

Supersonic refuse to cancel my fibre account. I cancelled the account at beginning of Dec 2020 and was told that my account will be closed on 31 Dec 2020. Received email and oh call confirmation. They deducted again at end of the month and I pH them everyday since 1 Jan. 6 days now and the same *********** excuse(they don't know why it's not deactivated.) They promise everytime to call back but never does. Do not sign up with them. The only thing they do effectively is to take your money at the end of the month.