Cannot logon to PMP450b

After the PMP450b SM has been running a day or so we can no logon to it. We get the following message:

You have timed out of your session, have been locked out due to too many unauthorized access attempts, or have exceeded your maximum allowed sessions.
Please press here to continue

Are you using a public IP address on the SM?

No. Private IP just like the AP.

Are you running the newest firmware R20.2.2.1?

Yes we are running the latest firmware.

I suspect that something or someone on your network is trying to get into the mgmt on these SM’s. Maybe start ratcheting down on some of the items on the security tab under configuration:

What is your “Session Timeout → Web, Telnet, FTP Session Timeout” Configured to? How many computers have web sessions active? They can logout to return a session, else it will timeout after that time.

I will have to have the user reboot as I cannot logon to the SM.

It is set for 10 minutes (600).