Contract phone

Hi, my name it's Perfect Rumbu, i took 2 contract phones with Telkom And i was told that the phone's will be around R400, that was not a problem but now the phone's stops working last month before end of the month, when i called Telkom was told that i need to pay R1550.65 for the two phones. so they debited that money in my account but was told that the phone's will cost me around R400. Can you please assist because was not told about R1550.65