Morgana's Ult doesn't break

I am going to assume this is because of the CC changes, but I just played a game where Morgana's ulimate was bugged. Morgana used her ultimate and then the target of her attack used Zhonya's. This would normally break the chain and the target would not get stunned. Instead, her target came out of Zhonya's after the 2 seconds and then was stunned from the ultimate and vulnerable.