eBucks with their incomplete and misleading marketing

Bought a product from istore in December and realised that I didn't get/earn the 15% ebucks I am supposed to. Upon chatting to someone I was told that it's because I bought from istore pre-owned. To my surprise when you read the "more info" about earn partners nowhere does it say excluding pre-owned or T&Cs apply, it just say istore and online. Once again FNB with their incomplete and misleading marketing