[Gameplay] Skills not working at game start

In a few of my games I have been unable to cast abilities at game start, including using summoner spells and items. This has occurred on multiple champions, if I recall correctly, Xerath, Caitlyn, and Cho'Gath (seemingly no connection). Leaving and reconnecting to the game fixes this issue- however, the problem is obvious, and I would like to solve it before playing and potentially ruining other games. I may redownload the game, I hope that solves the issue, but has anyone else had this?