Poor customer service

Went to game Jubilee Mall and bought Original Gardens System,when I got home I realized that the pipe doesn't fit and asked my brother to go back to Game and told them since I sent him there in the first place,they said bcos we opened the package they won't change or refund me,I want know as consumer am I nt entitled to my refund or my money, I want my money back and someone to call urgently on ***