Makro Voucher not recognized @ Makro Online

I bought a Makro stove 3 years back, 2 years later the stoves oven stopped working, Makro could not get this fixed and a Voucher was issued to us by the Centurion store.

Almost a year since receiving voucher we still trying to get a replacement for our stove, all store stocked stoves seem to be Gas+Electrical, which my wife does not want

So wife finds a Full gas stove online and we wanted to use our voucher to purchase this, it costs more than our voucher but we will put in the extra money, Makro online now tells us we cannot use the voucher on 'their online' store, i thought this was the same store?

Surely , Makro as a Business Should understand the position they have put me on, My stove was a full Gas, on all their Branches i have visited, none seem to carry full Gas Stoves, this has been for almost a year now and this Voucher is about to expire