I produced 2 Fouls, clicked on both midfielders it was to work on, the first one worked fine and completed the practice game quest. The second one just disappeared, I had clicked on them right after another so maybe it bugs if you go too fast? It disappeared from my inventory but the defender is still there and now I have to craft another one.
Not a huge deal, but an annoying bug if it's going to happen again, these event things trade for a good bit (for my level), kind of pricy to be having duds.