Pathetic service from MTN

My contract for my internet ends on 3rd August 2021. I call last week to find out about cancelling and I am told that they cannot cancel it because I need to pay R1526. I go today to pay R1526 and then I call again. I am THEN TOLD that they cannot cancel it because it only expires on 3rd August and MTN cannot cancel a contract in advance. They cannot set the date for cancellation on 3rd August 2021. I am also told sorry we cannot tell you how much you would pay when it ends. It could be double they say. Just wait for the next bill they say. I WANT THIS CONTRACT CANCELLED! Pathetic service from MTN. PATHETIC!