Private server crashes when someone enters the nether.

I run a small private Minecraft server that me and 3 other people were playing on. We just made a nether portal, but while entering the nether, the server crashes with no crash report. None of the nether chunks were loaded. After we started it up again, we were able to break blocks and see chunks, but item pickup was slow and blocks being destroyed did not register for a few seconds. The server crashed again. When I got on again I spawned at 8, 8, 8 in the overworld and was suffocating. The server crashed again. From then on the server crashed right when the spawn area was loaded. All crash reports are below as well as the last 5 logs. I am running java edition 1.13. My computer is running Windows 10 pro with a 64-bit operating system.

Thanks!