Try to do the following:
In \Program Files\wfavvid, you will find the file SubsystemRMCM.properties. Open this file using Notepad. In this file, make the following change to the agentUnavailRNA property: com.cisco.wf.subsystems.rmcm.agentUnavailRNA=true
Change to com.cisco.wf.subsystems.rmcm.agentUnavailRNA=false
Then save the file and exit Notepad. Then, during off peak hours, the engine needs to be restarted. You can do this inside AppAdmin -> System -> Engine -> Stop Engine, and then wait a few seconds, then -> Start Engine.
If you make this change, it is possible that ICD Callers can continuously ring at the same agent and never get answered if agent station is left unattended.