MTN cuts total line for late payment - Doesnt even open it for incoming calls

MTN - when you don't make your payment on time MTN just cuts your line. Not even keeping it on for incoming calls. THey just take you off from the network and then they still expect you to pay the FULL month premium for services. Even if you cant even use your phone or someone cannot even call you in emergencies. How is that right? I have now bought myself prepaid sims. Will just finish paying MTN until the contract is done and then im finished with them. I have been with MTN for 15years. I cannot take that they just cut your line. Yes I pay late, but I still pay for a full month services when I don't receive it or receive any credits for the days I didn't have service. Pathetic.!! Im so done!! What if im stuck next to the road and I cannot get calls or contact anyone? No man.