[GAMEPLAY] Guardian Angel bug

Multiple times now, I've had GA not work when being ulted by a yasuo or something similiar. It's really frustrating since it turns the teamfight around completely and I just lost my promo to it :(

Video proof: https://plays.tv/video/5a72582950fc23583b/proof-guardian-angel-bug-happened-multiple-times-but-is-only-time-have-evidence-