Waited 6 monts for response now I have to pay.

in December 2014, I bought a Blackberry 9720 at CNA Kolonade, 5 months after purchase the Device did not respond after charge, didn't go on anymore. Device was dead. I then took it back to CNA where I purchased it in middle May 2015. The salesman booked the phone to get checked out. After 2 months of constant contacting CNA, they told me the Device supplier is not Vodacom they'll have to send it to MTN, then again, a constant contacting, CNA to responded that they're awaiting MTN's statement, 6 months after booking the device for fixing, CNA contacted in Desember asking me to Contact MTN. So I did. MTN told me that my Device was water damaged and that I (the customer) should pay R300 for their services to get my phone back (still damaged). How if the warrantee states that you should bring in the device if something technical is wrong, should you as client get poor service and a non repaired device? I will not pay for a broken phone which they should have fixed and had to wait 6 months to find out that I the client will be liable to pay a fee for awaiting bad service? Please assist me in this matter? What am I to do in this situation?