Bad service

MTN is refusing to allocate my payment despite me sending them the proof of payment They don't want to give me a settlement amount They are debiting my account without a debicheck mandate. The amount that they are collecting is more than the agreed amount hence I never approved the mandate, when I asked their consultant he said the mandate is displaying the max collection amount and not necessarily the debit order amount. In my understanding I am supposed to see both I then said I will not accept the mandate. Came month end of Nov they debited the maximum collection amount without the an approved mandate. I asked them if this was lawful they have not responded it's been a month now. The statement are not reflecting the payment of R700 that I made. MTN I demand answers