Why Does a VoIP Phone Show the Wrong Extension After a Reboot?

A phone can register to a different extension after reboot if provisioning points to a shared profile, device assignment changed, or the phone retains stale configuration. Calls may then reach the wrong user or display incorrect caller identity.

What to check

Check device MAC assignment, provisioning template, extension credentials, DHCP or provisioning options, and registration logs. Compare the phone’s assigned profile with the inventory and test after a controlled restart.

Recommended next step

Correct the device-to-extension mapping in the authoritative provisioning system and securely reprovision the phone. Verify inbound and outbound caller identity before returning it to service.

How Informatix Systems can help

Informatix Systems provides VoIP and business communications services. We can review the affected systems and workflow, identify likely causes, and help plan a practical correction. Contact us with the platform involved, when the issue began, and non-sensitive error details.