repair of laptop

good day all<br> <br> I bought a laptop and a modem at cell c, and I used the laptop for only 2 weeks then the screen became blank called cell c call center to come fetch the laptop, they came and fetch it on the 11/11/2015 on the same day they send me the reference number REP684492 and the tracking number is RW***6. On the 16th I started calling them back asking them how far with the laptop and all the call center people they keep on transferring me to the repair center and at the repair center there saying they don't know were is my laptop and yesterday I decided to cancel their contract they said to me I cant cancel the contract because the laptop is at repairs and that I still have the modem and charger, told them to come fetch the charger and the modem and told them that they cant find it at repairs can you please help me to cancel this contract cause I am not happy with their service at all