While there may be a number of reasons why a landscape may not be processing events, this particular issue is specific to an error found in the OneClick/SRM Tomcat log:
Jan 05, 2018 00:39:38.988 (SRM/LandscapeManager/LandscapeThread_0) (com.aprisma.spectrum.app.repmgr.dc.event.handler.WirelessAPsHandler) - (ERROR) - Unable to properly process handler update.
Followed shortly after by:
Jan 05, 2018 00:39:39.045 (SRM/LandscapeManager/LandscapeThread_0) (SRM_Events) - (ERROR) - Database ERROR processing events for domain bdc1rcasdssap04. Will not poll domain