Mac App Store Promo Code not working in Spain

I generated and gave a Promo code to a customer in Spain. When he tried to redeem it in the Mac App Store Application, he couldn't and sent me a screen shot of the error.


"Tambien puedes introducir el codigo a mano.

Este codigo se aplicara a tu ID de Apple, xxxx@gmail.com"


The Text Box shows he has entered the correct promo code,

and then underneath in Red text is:


MZFreeProductCode.CannotRedeemiOSAppOnDestop


Has anyone else seen this? Is this a temporary problem or a Spain problem or an App Store bug? Who would I report this to?


(And the promo code is definitely not an iOS App promo code)

Thanks,