Overly billed

in July I took a contract online with Telkom for R349, August debit was successful but in September they couldn't deduct because my account was frozen of which i did call telkom request on making payment and I was told to wait until it bounces when it did I went and made payment of R350 at pick n pay, following month(October) i receive a notification that my account is in arreas I didnt pay any attention to that since i 've made payment, end of October still the debit order bounces since my case wasn't resolved, I went to make payment on the 27th of R400 now my account is suspended beacause I owe them R710 for penalties, I don't get it how did it come to that amount when I have made payments within the end of the month, why charge so much penalties, plus now the system is showing a different amount from the contract........Telkom services are terrible even the stuff can't give proper explanations on queries, I regret taking up a contract with them, please if you were thinking of taking a contract or any of their service just rather try another service provider.