Hustle for an exchange

I bought a phone on Sunday @ Orange Farm, Hisense U50 in the afternoon before the shop closed and was given a manual docket. When I got home the phone was not working when I tried swiping down or selecting data on the menu. On Monday around past 5, I went to change the phone store was closed. I tried to exchange @ Foschini @ Randburg square, the advised she can't assist due to the manual docket. She went to extra lengths to try and get hold of Orange Farm Foschini but the number doesn't work *** / 8300. She even went as far as asking on a group for a number and advised that she sent an email requesting for a slip. I went again yesterday got there at the same time as Monday and store was closed again. What I don't understand is that other TFG store were still open how this one store was closed, like they never opened. I want this phone replaced or my money back because it's going to be 7 days soon and this is frustrating. How is it a big company like Foschini have no resources.