Sold contract for R138p/m, paying over R400

Telephonic deal for R69pm x2 (sony exp&mediapad)through mobile talk- a Mohammad did the sale.Made sure I am going to pay once off R150 and thereafter R138p/m. Recieved goods on 13Oct15. Two debitorders for R150 went off (30/10&27/11)Then a R69 30/11and another R420,12 11/12.First bill from Telkom over R400.No one assist me after several emails to mobile talk and calls to Telkom. Got case nr from telkom on 14/12 (called them) and visited the Telkom store in Bloemfontein 18/12 and recieved another case nr were Telkom will call me back in 10 working days to assist me.Heared nothing yet.Want my recorded message as proof from Mobile talk were the deal was done.No one can assist me.Want to stop my contract-paying more,poor&pathetic service.Have a reference number recieved for deal from Mobile Talk on 29Sept15