All my users are facing this serious problem.
Please check file comment!
I’m in trouble please help me asap! 
Hi asus
Did you check the logs when the users trying to log on and what is showing ..
Also check under >radius monitor to see does your radius server how many users reject or accept ..
My opinion if the users get this message means there is no username to log on . But you saying after 5 or 10 attempt he can log in sounds strange for me.
Also check and crate local username on ppp and see does the users log on .
I hope this i been informed for you ..
thx
Selim
Asus, have you solved this problem? What was the reason?
I think whenever users reaches to their usage peak. UM & router are confused to authenticate new connections & after trying 5-6 times authenticate is accepted & if users reconnect thier 1st sessions is not disconnected in UM so they cannot connect is shared user is 1.
Also now please wait message remains for 15-20 secs.
this happens when above 200 users are connected.
Could possibly be, that UM cannot handle so many requests. Partly it could be because of large amounts of debug information written to log. In next release, debug log is reduced significantly. Also data base query performance is improved. So, if this is a performance bug (which could be possible, based on the fact, that you experience 40% CPU load on a Intel Quad Core, which should not happen for 200 active sessions), it should be fixed in next release.