Made4Business M Contract Account A***

MTN , when my contract ended, still charged me for a month , where they should only have charged me for the last 3 days of the contract date till expire date. I did try to resolve this with them by explaining and send them all the documents that show that they overcharged me but no luck, every time it is a different person who respond and MTN accounts people have no clue how their monthly billing work , they firs inform me that the don't charge in advance , till I proof to them that they do , then they ignore me or a differant person come back with just the same argument