The agent's phone device is not associated with a VoIP Monitor Server and there is no default VoIP Monitor Server selected.
To resolve this issue, perform these steps:
Select Cisco Desktop Administrator > Locations > your Cisco Customer Response Applications (CRA) Server Logical Call Center (LCC) > Enterprise Data Configuration > VoIP Monitor.
Ensure that either the agent's phone device is associated with the correct VoIP Monitor or the correct VoIP Monitor Server is selected as the default VoIP Monitor.
Note: Ensure that the correct VoIP Monitor Server is selected as the default VoIP Monitor only if it makes sense for that server to be the default. The majority of your agent phone devices need to be associated with that server.
For more information about resolving Cisco CRA and Customer Response Solutions (CRS), refer to these documents: