Overcharging

I am so gatvol of Telkom and their advisors who keep giving me different answers and I end up being *****ed I changed my debit date to the 16th because I'm not working anymore On the 5/10, they sent me an SMS advising I need to pay. Even after I changed my debit date. I went and paid manually on the 5/10 Only for them to debit my account again on the 16th. I reversed the debit because I already paid for this month. But now my next debit will be 250 more because I reversed. Why do I need to be punished when you wrongfully debited me. My account is up to date. You better not take 250 more. Yoh and the advisor had the nerve to tell me that when I miss a premium, I am being disrespectful so Telkom will come in my account anytime they want. Da****????? So I must pay twice a month???