Play Store Coupons recycling

Hi, these days I made the first release of coupons for a watch face on the Play Store. They were all taken but then only 60% were actually used (it’s been 3 days now). Since the coupons are not as abundant as on the Galaxy Store, is it possible to understand which codes are still not usable to give them to those who ask me for them? Thanks

I believe it is not uncommon for people to grab Play Store coupons and then sell them. Be sure you have an expiration date on them.
They will also ask for coupons for friends to give you a higher rating.

Samsung Developer Relations