A SIP message with invalid Phone Identity was rejected. Phone: %1 Cause: This can happen if the phone number is unknown or ...

A SIP message with invalid Phone Identity was rejected.

Phone: %1
Cause: This can happen if the phone number is unknown or configured incorrectly. This can also happen if the phone number(s) of the user are not configured correctly.
Resolution:
Ensure that the user and phone configuration(s) are correct.