Abilities not working !!!!

i played a game as Caitlyn a little bit ago and enemy swain was chasing me so i put a trap in his path , but he ran over it then after turned back and ran over it again and it still did not activate........

then the next game teamate blitz shot a grab at kha'zix and it went thru him...... and i was darius and more then half my pulls where dead on and nuthing also it refuse to ult several times ..