MTN worst customer services

During loadshedding and bad weather never services. Though I have paid them every month. The phone they gave me as a contract just switched off,I reported all these incidents to their Mondeor branch in Pinetown and elsewhere but to no avail. I decided to stop them from accessing my bank account, because I can't pay for service that I don't get. Suddenly after all this bad services and my doings,they remind me the last two months to pay them. My question, why do they choose to communicate with me now ? I even let them know to come and take their phone at my place of which they are in possession of my address. MTN I mentioned that I don't want anything to do with you.