Cancellation nightmare

On 24/2/16 gave notice of cancellation of Telkom Mobile contract (Service No. ***). Was given Case***8 as reference, with promise that someone would contact me. Phoned Customer Care Centre at 081 180 on 5 April and was again assured that cancellation would be attended to and I would be contacted. They tried contacting me on a number that doesn't exist anymore. Phoned again on 20 April and same story assured that a person will contact me. NOBODY HAS CONTACTED ME EVER AND CONTRACT IS STILL ACTIVE. I am still being charged for it and reminded to collect my upgrade for a contract I cancelled in February. Please assist soonest!!!!!