Wrongfully being debited for a contract i cancelled months ago

It has been months since i cancelled my contract with vodacom. They have proof of calls and notes made on the request to cancel my contract and i am still getting debited. I have called so many times to get it cancelled and get refund for the months i have been wrongfully debited. I am tired, every time i call to get feedback , i get told that the case has been escalated , when i send email i do not get response from the consultants i logged the query with