Vodacom Repairs

Hi. My sister took her phone for repairs (Vodacom Westgate) in the 23th of July 2020, last month we went to see the progress and we were told that they couldn't find the phone. They promised to call, we have been waiting a month for that call. The service is terrible, I mean how can u lose a customers phone and not say anything about it afterwards. They promised to return the phone in 21 working days, the duration has elapsed.