Groupon SA
Faulty products sold and incorrect refund

I purchased a ToMTom navigation which only worked a couple of times before it stopped working completely.
I requested a refund into my baking account, supplied banking details and then asked them to collect the faulty product.
They collected the item within two days and notified me that my Groupon account had been credited.
I responded one week ago asking why when I had specifically requested the refund into my banking account and have still not heard back.
If I had been at fault, perhaps missing an expiry date than a refund into my Groupon account would be fair. Considering the fact that I received a faulty product which of course is inconvenient in itself when it doesn't work at times you need it, a refund into my baking account is an acceptable request.