SHAME ON MTN

MTN are trying to dupe me in paying R8000 for a contract that ended last year. I have forwarded on numerous occasions my proof of payments, but still they are to trying to get me to make me pay again. I have a contract with MTN that ran out in 2022. I received a phone call from MTN with regards to the MTN Mega Gigs XL TopUp. I was told over the telephone that should I take the plan, the increase would be R30 on my current contract. I got a bill almost 3 times the amount of my contract and in the invoice it makes mention of Pro rata which was not discussed with me. Please share the telephonic conversation since all calls are recorded. They suspended my number, but still continue to bill me every month even though I can't use the number