Hidden fees

If i could give them a -5 i would but no option like that, i took a router from MTN on the 15th of June and they advised me to pay -R638.40 for the remainder of June and the rest of July as the month to month payment is R399, i did so same day even though i had issues with delivery from DSV but i received the package mind you i asked the giril i was talking to on the phone a couple of times that in July i wont pay a cent my next payment will be 4th of August for R399 she said yes BUT to my suprise i received an invoice on the 4th of July saying they will be deducting an amount of R 372.40 same day so in short MTN wants me to pay a total of R1,010.80 in less than a month of taking this router something i would have NEVER taken had it been mentioned on that call. They **** with all these hidden fees and i have written to their customer care and still waiting for response but rest assured i want them to CANCEL it and must come and get their router. LIES LIES LIES