Mazda Clear Water refuses to pay me my refund

I bought a right back window for my Mazda CX 3 Reg JH64MDGP at Mazda clear water, the consultant erroneously gave me a wrong window (Back window) which I paid R4500. Afterward they gave me the back right window estimate cost R2000. They have to pay me refund of a difference of R2500, every time I request my money the Dealer Manager ***) he tells me Mazda Southern Africa refuses to take the back window, so I won't be able to get my money up until Mazda Southern Africa takes that back window back. They are refusing with my refund me.