Game refuse to take back item in box still

I bought a children BMX at canal walk Game. After 3 days we decided to take it back. It was still in the box unopened. Since we live in Stellenbosch we decided to go to the Game store in the Eikestad mall. However the lady working in costomer service at first refused to take it back and said we must take it to the store where we baught it. After asking for the manager, Mr Quintin Japtha he apparently said that the BMX is not on their system and that we must come back the next day after they have loaded it on the system. It is now 4 days later and they still have not done that and refuse to help us refund the bmx.