my OpenFire hangs at one time about 3 or 4 days, it is installed on Windows Server 2008 and after that time users are disconnected spark that restarted your PC for example and again reconnect the system will not let spark indicates that the server is not found. To fix this I reboot the server, it is this, you can fix that.
Did you look at the logs on the openfire server? It’s probably the pep issue - You can find the fix in the announcements section of the forum.