No to MTN

I was called repearedly by MTN to upgrade my 3x cellphone contracts for my kids. I did ask specifically about the old contract expiry and when the new contracts will kick in and we're told the new contract will replace the old one. At the end of the month (January) I received an enormous bill. When I queried the bill I was told that the new contract kicked in emediately and that both contracts were billed for for January and they will not reverse it. I also complained about the itemized billing that were all of a sudden added to the accounts which I didn't asked for. From January untill now (April), I receive bills with Itemised billing, extra data charges, extra contract bills (3× additional contract bundles on one number) and still itemized billing. I call every month and nothing changes. I have blocks on the numbers for additional charges but still I get billed extra. PLEASE DO NOT USE MTN. I have been a customer of them for almost 30 years but it is time to cancel my contracts and move onto a different service provider as they don't care.