Linux Server Freezing

I don’t really know how to explain this. Server sometimes just… Freezes. it can’t autorestart because task is frozen. it dosen’t respond to anything. it’s just dead. i must manualy connect to server via ssh or anything else and relaunch server. last things in console is totaly random. round start, mid round people talking in chat, just totaly random. Timing is also random. sometimes it happens 3 times a day. sometimes 5 days without freeze. if anyone has any idea what causes it please post im so sick of this.