Bad Bad Bad service

I have a contract with Telkom Mobile and it has been a nightmare from the start. the reason that i took this contract was to assist my Son because they have a group chat in class for discussion , but guess what ? he was uable to download whattsapp so it was useless to us, finally when I called them i had to sit on the phone for 3 hours trying to sort the matter out and it was still not resolved a call had to be logged with back office. finally after a week and half we receive an email that says we can now download and not today the 15.05.2016 i am calling telkom mobile to increase the data limit i am told that i owe the R425.00 I DONT WHERE THAT IS COMING FROM BECAUSE WHEN I TOOK THE CONTRACT I GAVE SPECIFIC INSTRUCTIONS THAT I WANT TO PAY R139.00. Can i get someone urgently resolve this because this is really bas. who gave telkom an instruction to increase the spend limit ?