Billed for a contract and phone i dont have

I January i walked away from a cellphone and contract due to extremely poor service which i reported via their sms feedback system - NO FEEDBACK FROM THEIR SIDE. February i got billed for the contract and phone and then March i get billed for the canellation of the contract a wopping R6500.00 this caused my account to go in arrears and all my debits to bounce back!! Now im sitting with R1300.00 bank charges for all the debits that bounced!! I want my February money which was debited and reimbur*****t for all my bank fees now!! This is unnaceptable!! Why must i pay for your mistakes!! This was reported on the 2nd April 2015 *** but i have still not gotten any feedback!