I am seeing this issue as well from time to time - found it also on the latest stable version too:
Lucee 5.2.4.37 Error (java.lang.IllegalStateException)
Message The resources may not be accessed if they are not currently started
Stacktrace The Error Occurred in
/admin/overview.cfm: line 170
called from /admin/overview.overview.cfm: line 1
called from /admin/web.cfm: line 392
called from /admin/server.cfm: line 2
Even though restarting Lucee corrects the issue it would be good to have a better fix for it.