MTN Retention lack of service

I have been trying to call MTN about my contract that expired end if June and I called on 01 Juky to cancel it but it's still not cancelled. When I call the linevforvtge past 2 days but when you call the line/option for upgrades they pickup immediately, when you call the cancellation line no one picks up. They seem to be interested when you're talking out a new contract/debt, and dont want to service the customers who wants to get out of contracts.