Fell out of world

Me and my brother were both exiting the end city and it teleported him to under the end and he fell out of the world and lost everything. So I built a chest and put my stuff in it before I went through. I survived, so I went back and got my stuff. I went through the portal just like the time before and I got teleported out of the world, lost all my stuff, and like 15 hours of my time.