When we try and send a message to a 7921/7925 phone.
We get this error message in AMCOM "Unable to send message to #MAC# due to no IP address. The device is either off, recently turned on, Unregistered or not within the CUCM"
The Amcom message goes through but we get no alert on the phone that we received it .
It was working fine didn't make any changes to Call Manager.
Amcom Messenger V5.5.6
CUCM V8.5.1
Has anyone had the same issue?