Additional services charged on an expired contract

My MTN contract expired end of August 2020, I was paying R190.00 for 2 lines. On 2 separate occasions (I think in July and August) I was called by MTN agents to renew the contract and I clearly stated “I am not renewing my contract”. I am told the contract was not cancelled, apparently “I never cancelled” because the renewals agents do not deal with cancelling contracts and they were not at liberty to tell me that additional services on my contract will continue even after my contract expires. Beginning of September, my 2 lines where then both credited with 10GIG each and I was charged R1 138.38, then my bank account was debited with the amount on the 21st of September. I reversed the debit order because I had not renewed the contract so I did not owe MTN anything, especially not R1 138.38 after paying R190 for 2 years, on 2 lines. MTN then suspended my numbers for nonpayment without communicating, I just noticed my phones not working anymore. I went to the MTN store in Sandton City, made calls to MTN several times and have multiple tickets opened, that I just get SMS’s stating “dear customer, your query has been closed” without any communication. I have to keep calling to get feedback and to date my query is still not resolved. MTN insists that I owe them R1 138.38 and it’s actually increased to R1439.84 now, I’m not sure why and how as I did not renew the contract. You can’t say the contract has expired but additional services that were part of the contract continue even after the contract has expired, then you charge a customer normal rates and your explanation is, when the contract expired the promotion ended and normal rates kicked in? What does that even mean? I was never told that when my contract expires the promotional data will continue to be loaded to my numbers, but charged at normal rates until I call MTN to cancel. I never requested 10 GIG to be loaded on both my lines so I can’t be charged and forced to pay for a service I never requested. I’ve requested for the 10 GIG to be reversed but you refuse. MTN please be fair, when a customer’s contract expires all additional services provided should end/stop, you can’t use ********* business practices to force a customer to pay for services they never requested. Please reverse the 10GB provisions, on both numbers and cancel my contract. If you can’t do this, provide me with a deadlock letter, so I may take matter to the Ombudsman.