The VCC agent receives notification (flashing indicator) that there is an inbound call, but VCC status immediately goes to "Offline".
Virtual Contact Center (all platforms) in a corporate office environment or remote / residential network.
Please complete these steps to establish and verify VCC agent's audio path: How to make a verification call from the Agent Console Profile
Desk phone user: there may be an invalid or missing Workplace Phone Number in the VCC agent's profile.
Bria user: the Workplace SIP URI may not be entered correctly or the Bria software is offline.
Clearing browser cache / cookies on a regular basis can also help prevent this issue from happening.
If the VCC agent is still unable to receive calls on their preferred or default endpoint after completing the outlined steps, please check if the agent (for testing purposes) can log into the VCC Agent Console on another PC or test in another network. Now have the agent do a verification call to the preferred workplace phone number.