7 Days return policy - Absolute lie

I went into the Clearwater branch on Tuesday 3 March 2015, I was helped by a very helpful consultant - unfortunately can't remember his name. The Sony Experia Z3 was the phone I chose as my upgrade and I was told by the consultant that if I have any problems within 7 days I can return the phone and it will be replaced. I returned to the store on Saturday 7 March 2015 because the phone's screen was just blank and it was obvious that it is faulty!! Maketzi booked in the phone and at first I was very surprised that I was told that the phone now had to be sent for an assessment, 4 days after I received the phone!!! Being understanding I said ok and I was promised feedback latest Wednesday 11 March 2015. I have phoned Maketzi several times and managed to speak to him twice, every time with still no feedback or he is out on lunch or whatever, personally I think he was just avoiding my call!!! This is ridiculous and makes me understand now why Vodacom are loosing so many customers. My wife upgraded with Cell C and not a days issue and only great service, Vodacom can learn a lot from their customer service and not make blank promises or gaurentees that can't be met!!!!!