...

Are the cards there when you look for them in your inventory instead? What game is it?

Works for me

you probably got logged out...

Mine is fine, just got a card in fact.

However, I've had that problem previously and I thought the reason was just a lagging internet connection. Tried again a little later and everything went back to normal.

I had this problem once. Waited a couple of hours and the problem solved itself, I guess the badge page just bugs out at times