Caitlyn E is glitching when interacting with stuns

I have noticed that in the past few games I have played as Caitlyn, her E is interacting strangely with both Taric and Leona stuns. Sometimes it will go off fully (the projectile will fire, do damage, and apply the slow, and Caitlyn will be knocked back) but the stun will still apply at the end of the movement. Other times the projectile will fire but do no damage and not apply slow, and Caitlyn does not get knocked back but is stunned in place. Then sometimes absolutely nothing will happen with the E and Caitlyn will be stunned but E will go on full cooldown as if it went off. This bug has become increasingly frustrating, and I would appreciate if it could be addressed soon. Thank you.