Server shutting down due to ERR

[PoppAUS]

Any suggestions for this fix? Our server is constantly rebooting due to this error. We have not made any changes (we don't think) in the last couple of days.

User logs on. 

2021-12-22T00:15:04 81.123 WRN Entry missing 'platform' or 'userid' attribute: <player id="76561197971084492" lastlogin="2021-12-21 17:22:36"><acl id="76561198123593112" /><acl id="76561198115280024" /><acl id="76561198381327631" /><acl id="76561198159960504" /><acl id="76561198072537580" /><acl id="76561198282859916" /><acl id="76561198177943706" /><acl id="76561198085614525" /><acl id="76561198004811290" /><lpblock pos="1500,71,626" /><bedroll pos="1501,72,622" /></player>
2021-12-22T00:15:04 81.123 ERR player-entry has missing or invalid user-identifier attributes: <player id="76561197971084492" lastlogin="2021-12-21 17:22:36"><acl id="76561198123593112" /><acl id="76561198115280024" /><acl id="76561198381327631" /><acl id="76561198159960504" /><acl id="76561198072537580" /><acl id="76561198282859916" /><acl id="76561198177943706" /><acl id="76561198085614525" /><acl id="7656119

Then starts the shutdown/quit process. 

[dimko]

I am not a fun pimp.

I do some WILD speculation.

HairyOldGamer - https://steamcommunity.com/id/HairyOldGamer/

Is this guy joining your server?

Do you recognize him?

If he DOESN'T join, is problems same? is it still happening?

What is error message then?