Bad service

I returned my tv that I purchased at game zewenwacht in july, as it had a defect in the screen in september, I purchased the tv on sale for 3995, value 4799. I have been given a gift voucher worth 3995, that I can only use at game, which I cannot even use to purchase the same tv as it is worth more and no option of a cash refund, which is unfair as this is the 2nd ina space of three months returned. I want the value of the item purchased back as I am losing on this **** deal and service.