couldnt use any moves

I'm carrying a game as panth i get a penta, team stole penta, were winning everything by a lot and then all of a sudden i couldn't use my moves (q,w,e,r) so when this normally happens i relog so i did and still no so i exited league the whole page and then re-oped it and logged in cuz that has to work and still nope and by now my inhibs are gone and i couldn't even auto minions so i tried one last time and i exited the game a reconnected and i couldn't do anything again and by now they are taking my teams inner turrets and i couldn't do anything so i sat in base angry and watched as i lose my last promo game again.. this is really annoying cuz i know that wasn't my internet connection or anything cuz it was fine all game and i could get back in game fine that was my game to win i even got a penta