Contract upgrade Breach of Contract

My contract was due for an upgrade so I thought I'd run into the vodacom Shop in Brooklyn. <br> <br> I decided to upgrade to a Samsung S6 edge with a screen cover and a 7 day replacement warranty. I walked out with the new handset and a new 2 year contract.<br> <br> After an hour of operating the handset the screen started to flash red and the class screen cover (R500.00) also came off. The next day I took it back and they said I should send it in for repairs, a new replacement handset was promised by the store manager. I sent it in Tuesday(27th) and they said to have a turnaround time of 4 days. After calling them several times after day 4 they couldn't manage to find the handset. <br> <br> Eventually they said the original handset will be returned to me.Today, 8 days after sending it in I still have not received a (old or new) handaset. I will still have to pay the full invoice amount by the end of the month even though I have not received a working device after signing. <br> <br> Shouldn't they stick by their contract and replace the device? <br> <br> Vodacom draws you into signing a 2 year contract and makes you cough up each month, when i'ts their turn to help they only disappoint. Don't ever sign a 2 year contract!