Why Does a VoIP Phone Show Busy When the User Is Available?

A phone may report busy because of call waiting settings, presence state, forwarding, an active session, or stale registration. The behavior can vary across devices linked to one extension.

What to check

Check call status across all registered devices, presence and Do Not Disturb settings, forwarding rules, call waiting, and recent registration events. Test a controlled inbound call.

Recommended next step

Clear the verified stale state or adjust the intended call handling, then retest all devices. Informatix Systems can troubleshoot VoIP extensions and presence.