Vodacom poor service

I took out a contact 10 months ago with vodacom, within the 1st 7 days i took the phone back to the n1 city branch, the manager refused to take the device back, over the past few months i have taken the faculty device back and forth to the century city branch, they have sent the device away for "repairs" more than 4 times, yet the device remains faulty! I am paying for a faulty item, vodacom refuses to provide me with a new device! Poor service! Wasted my time, money and effort! please contact me ASAP