Exploitation of clients

Telkom didn't debit on the last day of the month of May which I then called in to find out why they didn't debit my account then the lady said they had technical issues... Then I arranged that they should debit double for the month of June.... Which they did now tell me why from July I have been paying extra 256 rands plus there is a r699 which I don't know where it comes from.... Every month my sum card is being blocked yet money is being taken from my account?? They said to me my account was handed over to collections I asked them how is it my fault that they didn't debit they couldn't answer me.. Anyways I'm tired of you guys taking advantage of me as if I don't work hard for my money... You guys literally debited me 1181 rands for August and I asked no body provided the answers for me... I regret ever taking a contract with you... BTW I pay 740 rands monthly for the telkom cellphone contract. Now I have to struggle doing literally anything because I am overcharged for a fault I know nothing about...