World crashes near ocean monument when open to LAN

Whenever I swim around or walk around (I made a bridge) an ocean monument, I'm fine, but when I open the world to LAN and then walk around, I occasionally crash. Other people do not have to be next to me. They just have to be playing the same LAN world. It will crash whether or not they're with me near the monument, but it only crashes if they're online. Sorry I didn't take any videos or anything.