Resolve Webex Calling for Government Call Queue Agent Not Receiving Calls Due to Device Registration Issues

Issue

A call queue agent was not receiving calls routed through the queue, while other agents in the same queue were receiving calls successfully. The affected agent (+11231231234) was configured as the last member in the call queue flow but calls were not being extended to this agent. When test calls were made directly to the affected agent number, the calls completed successfully, indicating the phone itself was functional. However, when calls were routed through the call queue (+11231231111) with final destination the affected agent (+11231231234), the caller would hear "all agents are busy" or fast busy instead of the call being offered to the final agent in the queue.

Call samples showed that queue calls were being extended to multiple other agents (+11231232222, +11231233333, +11231234444, +11231235555, +11231236666, +11231237777) but not reaching the affected agent at the end of the queue sequence.

Environment

• Webex Calling for Government (FedRAMP Moderate)

• Federal organization using Control Hub

• Call queue configuration with multiple agents in sequential order

• Shared-line devices including Cisco 9841, Tablet, Desktop, Mobile, and Hot Desking endpoints

• Call queue using longest idle routing method

Resolution

The issue was resolved through these steps:

Step 1: Device Registration Verification

Investigation showed that the some agent devices (Cisco 9841, Tablet, Desktop, Mobile, Hot Desking) were not registered at the time of the call samples. This condition resulted in a "Temporarily Unavailable" response when the call queue attempted to route calls to the unregistered agent. However, the call was never extended to the affected agent (+11231231234) who was configured as the last member in the call queue flow. The "Temporarily Unavailable" would not cause the "all agents are busy" or fast busy response. When calls routed through the call queue (+11231231111 and reached final destination the affected agent (+11231231234) this is when the caller would hear "all agents are busy" or fast busy since the call was never offered to the final destination agent in the queue.

Step 2: Agent Reconfiguration

The resolution involved removing the affected agent entry from the call queue configuration and then re-adding the agent:

1. Remove the agent (+11231231234) from the call queue configuration.

2. Re-add the agent to the call queue

3. Verify the agent is properly configured and available.

Step 3: Validation Testing

After re-adding the agent, a test call was performed to validate the resolution. The test call successfully completed to the previously affected agent, confirming that calls were now being properly routed through the queue to reach the final agent in the sequence.

Step 4: Monitoring Period

A 72-hour monitoring period was implemented to ensure the issue did not recur. No further incidents were reported during this monitoring window, confirming the resolution was successful.

Cause

The root cause was that the affected agent's shared-line devices were not properly registered with the Webex Calling for Government platform. When a call queue attempts to route calls to an agent whose devices are not in a good registered state and the agent is the final destination agent, the system did not extend the call to the final destination agent's number +11231231234" and the Caller received message "all agents are busy" or a fast busy signal. The device registration issue of the final destination agent prevented the call queue from properly distributing calls this agent.

Related Content

• Webex App | Change your call queue status

• Cisco Technical Support & Downloads

Revision History

Revision	Publish Date	Comments
1.0	10-Nov-2026	Initial Release