I guess Blue icon represents Non-ACD call, which can be personal calls for the agent that can be reached by dialling the agent's extension which are not coming through centralized IVR/Queue based routing.
The blue agent-state icon can indicate one of two things:
The CTI Link is "reconnecting" - i.e. the operator does not currently have CTI capability. The CTI Link will attempt to re-establish connectivity (based on its configuration). Once connected, the agent-state will be refreshed and updated on the toolbar.
The operator is logged in without providing an agent ID and/or there is no agent logged into the extension associated with the operator's CTI login. Agent state cannot be changed, but the operator may receive screen pops (depending on the CTI platform).
If the condition occurs for all Pega Call users on a node, it's likely #1 above. Check for network errors between the Pega node and CTI server.
If it occurs for a few users, check that they logged in with agent id and did not logout from the ACD using some other tool.
For case #2 (aka monitor mode), we changed the icon in Pega Call 18.104.22.168+ to be the green logged-in icon when we added simple telephony mode. With simple telephony, agents are usually managing agent state through another tool and the icon conveys if they are connected to CTI or not (vs reconnecting as in #1 or logged out).
Harish, you are referring to the blue call state icon - that is different. OP was referring to the agent-state icon.