Service Not Being Cancelled since November 2014

I Send a cancellation letter to [Email Removed] on the 7/11/2014 to cancel all services with ADT, i got a email back from ADT with my Ticket No - ED6AA5C542E1C. Months whent pass just to find out from my accounts dep. that ADT was still debiting our bank account, and thus after i had cancelled all services with them! So i phoned there call center (what a joke) on the 28/7/2015 to found out what the hell is going on and spoke to Lindiwe Khumalo, explained everything to her and mailed her the original email i send on the 7/11/2014, nothing happened. Then next day i phoned spoke to M.P. Smith jet again explained everything and had to mail her the same cancellation email from 7/11/2014 and jet again nothing happened. On the 3/8/2015 i phoned again and spoke to M.Kosiyane same story explained all to him and mail him and the other 2 ladies again because according to him he said they never received the mails, i told him that every time i had sent an email to ADT i got my delivery report and read report and he had no answer. They say they will call back that never happens how do i sort this out if the call center is full of ******s working there. stay away from ADT service is bad!!