[GAMEPLAY] Yasuo gains a shield when Ulting(?)

Throughout my last match against a yasuo, a number of times, he gained some part of his shield when ulting, even though it was clearly disabled due to the incoming damage (the wind shield goes away when you simply auto-attack, which I always look forward to doing). After contemplating if the summoner was hacking, they feigned ignorance, but I reported anyway incase they simply wished to avoid guilty verdict. However, if I am wrong however and instead it truly is a bug, then I truly hope your technicians get to the bottom of this as this bug cost me my lane due to the snowballing of Yasuo.