[GAMEPLAY][ARURF] Lissandra Ult not working

Hey, two days ago i played a ARURF match as Lissandra and encountered a rly game breaking bug. After i protobelted into the enemy Ahri and Ulted my self on top of her i only did minor/no damage to her and on top of that i was still vulnerable and targetable so i recieved the full dmg from her in my Ult. I can't confirm if that Happens everytime because i only Played her Once in ARURF. Would be nice if the Devteam takes a look into this :)