Billing incorrectly & no contact/communication

I have had a never ending list of problems since applying for my account with MTN which was only sorted after i logged a complaint on Hellopeter.com previously. My router has not been working properly since April last year and I have been billed ridiculous amounts since. I had a query logged with MTN and was then told that I will not be billed from the time my account was paid off for the initial two months which was July last year. The debit order went off every month and the account has been paid on schedule. When I the customer care last week I got an automated message saying that my number is not linked to a valid account. After sending an e-mail I was told I can phone, I got through today to be told that my account has been with legal since April 2015? I was never contacted or informed of this in the last 8 months? Nobody can help me and it seems that every time I phone or go to a store that each person is more *********** than the next (if they don't have a bad attitude and does not want to help you to begin with!)