[GAMEPLAY] ability bug lux

i just came out of a ranked game i was playing lux. i tried to E a minion wave halfway true the animation the moment the spell is spreading out over the minion wave the spell dissapears and my ability gets greyed out like i havn't learned the spell yet. i reconnected like 5 times but didn't help so i had to play the next 30 min of game without my E :(