MTN what a poor customer service

MTN sold me incorrect product they debited my account, extra I don't mind that, i did not use their sim card for data at all. i want to cancel the contract they cant they taking me pillar to post, contract was for R399 they debited R597. I dont want my R579 i want to cancel cause its not what was sold to me i dont need this simcard its not even a month having this sim but they cant cancelled, went to key west mtn they gave me number to call they cant assist on their side call number *** no answer call 083 135 spoke to Lungile could not assist send me to Retention I have hold for more than an hour no answer. Never seen such poor service in my life