Hi Masahista and welcome to the forums 
Given that it is Friday evening, you won’t get a reply from Funcom until at least next week, so i thought I’d try to save you some time.
Funcom reps will suggest one (or both) of two things - either they will suggest that you go to the discord for Private Server owners as they will be more likely to be able to help you - Admins United: Conan - Discord for Server Admins! - or they will ask you to check whether the problem occurs without mods, as it is quite possible that the problem is being caused by an outdated mod or mod mismatch.
I don’t have experience of how to test mod issues on a private server, but in singleplayer this would be done by removing mods and adding them back in until I was able to isolate the one causing the crash - maybe it is possible to do something similar on a server?
I hope something here helps.