MTN basically *****ing! Cancel my contract!

Such a painful experience to cancel my contract! 5 months later (with cancellation calls in the past 6 mnths every single month!), I still have the debit order going through after I am told that the number has been moved to prepaid and contract is cancelled, Every time I spend hours on the call 135 and they transfer me from department to department with no help, contract is saying they cant view account its on prepaid and prepaid says the number is on contract. No body can help, I was told to call 808 - it does not work! I was called to contact retentions@mtn - the email does not work! So exhausting!