Cellphone Cover Return - Samsung Refuse

Extremely disappointed In Samsung Mobile South Africa. I purchased a cellphone cover 5 days ago from your Samsung Store and my mother purchased me the same cover. Now I am sitting with 2 of the same covers. I phoned the store to get a return and they say I cant return it for cash I can only get a credit. I don't need anything else from the store. I bought a R11 000 phone and a R400 cover infact 2 of them now they cant refund me for 1 Cover they expect me to buy something else. I DON'T WANT ANYTHING ELSE. Shocking is what its called. Don't buy from Samsung as they do not give cash back. Take your money elsewhere!!!