POOR SERVICE TELKOM MOBILE

Am very disappointed about telkom Mobile service. I took a huawei contract phone from telkom in 31 dec 2015 which goes for R199 including the phone, 100minutes, 1GB data and free WiFi. End of January i was debited R475 i call the call center they explain by sms it was a mistake and hence i will be credited the following month. End of February another debit again R318 i called the call again now they said the phone is 199 and the data 118. But this a contract phone for R199 including all the data and 100min why are they over billing and not refunding my money. If telkom cannot manage their services they must close the company rather providing such poor service!!!.