Server turns off after players join

Mohist 1.12.2

Hello guys! My friends server keeps turning off when he joins, he said that had been starting to happen this week, atleast 3 times, but the crashes weren't instant, It was atleast 15 minute before crashing.

Here's the Log: https://mclo.gs/HNhriWA

And crash report: https://mclo.gs/WoKTsGp