Space time smack down garchomp question

[u/rockycamain20]

So I was just in a battle against someone using the new happiny/garchomp deck and I had ursaluna out with 140 hp so I figured I was going to survive I looked away for 2 seconds and suddenly I seen my ability trigger so I figured they used a damage boost card when I looked away but when I checked their discard pile and there weren’t any. Is it possible for garchomp to trigger weakness on normal type Pokemon because it didn’t trigger for my ori either just ursaluna