MTN Billing disaster

Last month on the 25th January 2021, MTN decided to cut my contract lines for non-payment. When i went to a branch to find out why, i was told they have implemented a new billing system which requires that i pay in advance every month. So last month i paid double my normal instalment on the 25th January 2021. i had to pay for January 2021, 5 days before the end of the month and for February 2021 fully in advance. Why such a system change is being implemented toward the end of my current contracts is a mystery to me. It is also very pecu**** why you would force a customer during these tough economic times of the COVID pandemic to pay double an instalment when not in arrears. I'm not even sure if its legal or ethical to change a contract like that towards the end of its current term. I've had many successive MTN contracts over the last 10 years.and i have always had to pay before or at the end of the month. This has now changed apparently. That's the first problem. The second problem, which is even worse, is they have now sent me an SMS saying i need to pay on the 17th February 2021 or they will cut the lines. This morning i wake up to another SMS saying my lines have been cut. This is ridiculous because, last month i paid double to include February 2021 (the whole month), now i'm being forced by cutting of my lines to pay for March 2021 almost 2 weeks before. In what world is that fair or even considerate or realistic. I'm a business owner who relays on my phones to generate the very income i use to pay MTN. But it seems there is very real and blatant disregard for people's livelihoods or loyalty (10 years plus having contracts). This is very regrettable and disheartening. I humbly request that this be sorted out as a matter of urgency.