I ran into this issue when I was trying to Create Advanced Session with the Epic Online Services Online Subsystem:
LogEOSSDK: Error: LogEOSSessions: bPresenceEnabled requires a valid local user.
LogOnlineSession: Error: EOS: EOS_Sessions_CreateSessionModification() failed with EOS result code (EOS_InvalidUser)
This is due to the fact that Allow Invites is true by default in the Create Advanced Session node and in UE 5.2.0 this results in bPresenceEnabled being set to truedeep underneath, which will then prevent a session from being created because there’s no real user on a dedicated server to enable presence for.
In UE 5.2.0, these have to be set to false (unchecked) in the Create Advanced Sessions node for a dedicated server to be able to create a session: