I bought 2 gift card...

I bought 2 gift cards to the value R500, no one told me they expire.. Few weeks ago I went to the store and I was told the cards have expired. Upon purchasing them, no one told me they expire, it was a huge shock when I was told they've expired and can't do anything about it. How do clients loose money like that, where is openness and transparency? Surely if they had told me upon purchase that the cards expires, I wouldn't have kept them longer. Is this the way to rob clients clicks?