Refund of the product that have multinational problem

Good Day Can you please help me to get my refund back from Game Store at eastrand mall, i bought the airfryer by the brand name of Bennett Reader from them last year may 2024 towards November 2024 i took it back to the store since it was giving me the problems it couldn't function as it supposed to and i hardly use it, they took it back to Bennett Reader to be fixed and they called me to come collect it in December 2024, i tried to use it again this year and it's still giving me the same problem i encountered before, so today i took it back to the store and they refused to give me back my money and i don't want their product anymore.