torn apart change

I bought 2 cool drink on Saturday 21 January with R100 note ,,,,,then the guy give me a change which was R58 that I didn't put my concentration to ,,,,,Sunday late I realised that the change the give me is a torn R50 and I returned it Monday morning,,,I got this manager who was very Ryde n she said I can take it up anywhere I can but she won't exchange my money,,,,,,I can not use it anywhere and reason I didn't check it was because I had my baby with me