I compared logs from previous version of server (4.19) and current.
On previous server I got on Login reguest the following:
?Name=PlayerName userId: STEAM_ID
But on new (4.21) server I got this:
?Name=PlayerName userId: Steam: STEAM_ID (with zero at beggining)
Basically, userId is empty on the new server, and SteamID is the same but with 0 at beggining.
On old server userId is SteamID
Now userId just empty instead of SteamID.