Valve requires its own Game Server Login Token (GSLT) for every public CS2 server.
- Open steamcommunity.com/dev/managegameservers with your Steam account.
- Enter App ID 730, add a note and create the token.
- Enter the token when ordering – or change it later under your server → Startup variables at
STEAM_GSLT. - Restart the server.
The Steam account must not be limited (at least one purchase) and must not have any bans.