Triple deduction from my account:Telkom

I have a contract with telkom, what happened is that I am no longer getting paid on the 25th I get paid on month end it's been a year now but they were getting money every month when they go to my account,apparently last month they did not get their payment on the 25 and they did not send me communication to advise me about the missed payments, most of the 3rd parties advised me and I was able to deposit for them.why they kept quiet all the time on months end there was money they did not debit if they really wanted to debit, to me it's like they were waiting for days to pass so that they can over charge me I have never missed a payment with them they know it very well.

The worst part they debit R759 from my bank my premium is R277 I dont know why they are debiting so much money. I am deeply hurt they took money that was suppose to buy nappies and food for my child who is 6 month old I am very dissapointed with their service. I am left with nothing in my bank