Unhappy loyal customer

Not even worth 1 star. I was called by 1 of your consultants on the 17th April to migrate my account with additional minutes and data for an extra R80.00. Ever since the migration took place my line is barred from making calls to any Mtn customer care number. I haven't been able to receive incoming calls either. The only time i am able to contact your Customer care is after 5pm when neither of your consultants are able to help me. And today to my horror i receive a bill of R632.18 prorated 17/04 - 11/05. I am not paying this account. I was told there would be an additional charge of only R80 otherwise i wouldn't have opted to migrate. Mtn kindly contact me as i am putting a stop to the debit order. I cannot afford a bill of R600 for less than half the month!!!