Bad attitude and appaling service

I upgraded my cellphone contract last Friday and was told the new sim would be activated in 24 hours. By Monday the sim was still not active and I had to go in to the shop to query this, and eventually it was activated on Tuesday. From Tuesday till Thursday the phone wouldn't work. I experienced a lot of dropped calls and silent connections that made me realize that there was definitely something wrong so I went to Vodacom and asked them to take investigate. They said they couldn't do anything and I had to leave the phone and it would take up to 21 days to get it back. This is a brand new Samsung S6 that's given me problems from day 1. At one point, I spent 2 hours in the bayside shop just to get data settings configured and the staff did not seem knowledgeable about how to go about setting the phone up. It's only been a week since I upgraded to my S6 but I have been to the Vodacom shop 6 times already just to try and get some assistance to make this phone and line work. Their service and the attitude of the consultant is very appalling and I am not a happy customer at all!