Billed incorrectly

I need assistance with the correct bill amount so I can proceed with the payments. I have 2 contracts with MTN, phone, and Sim only for data. On the Sim only I have been billed twice, contract amount of R299 as usual plus R287 for a month to month basis. When I upgraded the Sim only contract I was told it was unsuccessful as I was still provisioned with the old data package. I then received an SMS ing my contract has expired I will be on a month-to-month basis, when contacting MTN to cancel the contract I was told the upgrade was successful yet I had never received the new data provisioning. I’m currently billed R857 for last month and this month also, I’m failing to make payments and my number has been suspended. I have been going back and forth with Mtn and no one is willing to assist. Ref 5414627. I need a correct bill and I don’t want the Sim only package I want to cancel it and I won’t pay the cancelation fee as I have never benefited from the upgrade. I want to make payments I need the correct bill.