Double check your Badges page to see how many drops you have left? Looks like you have 2 non-F2P games and more than enough playtime to have earned your alloted free cards for them. If you're not sure what to look for, This Image might help. The yellow boxes show how many drops are remaining for each of the games, notice that Binding of Isaac is listed as having 0 drops remaining which means further idling of that game will not result in additional cards.