[GAMEPLAY] Lux's E unusable in ARAM most of the game.

A pretty devastating bug occurred during an ARAM match where Lux's E became unusable and greyed out, saying "You cannot use that spell right now!" The tooltip also said it cost 0 mana.

This lost me the game and this was very lame to experience as Lux.

Restarting the client did not resolve the problem.

Reporting Rito x9.