Jinx keeps using substitute even tho it's at 1 bar of health

While fighting a trainer who was using Jinx after lowest it's health to 1 bar. It keeps using substitute which take all damage for the next turn.

I can't leave the battle because it's a trainer and Jinx won't attack so I can't die. So I'm stuck. The after disconnecting, I can no longer connect without being kicked due to flying.

UPDATE
After fully closing Minecraft and launcher. I was able to connect successfully and get unstuck from the battle.