Ok, so it seems to be an isolated issue. The trac.log usually provides more information, but it’s also worth checking the other .log files. I don’t know all of them in detail, so it’s a good idea to try to reproduce the issue, collect the logs, and send them to TAC for analysis.
In SmartConsole, did you find any relevant logs about this user’s failed authentication attempt? If so, please let us know what they show.
Is the number of Office Mode IPs within limits? Sometimes it can reach the maximum.
When the user tries to authenticate, what error message is shown on the endpoint?
It would be helpful to schedule a new call with the user and collect evidence while they try to connect. Try to capture as many logs as possible at the moment of the error, check them in SmartConsole and in trac.log, and make sure that Enable logging – Extended is enabled when running it️