It may be the firmware see
https://mitel.custhelp.com/app/answers/answer_view/a_id/1010319/1378803773 Cause
69xx sets are preloaded from the factory running 1.3.1.37.
This allows Mitel sets to connect to cloud services without the appropriate DHCP options ie option 125, RCS programming or MDNS.
69xx phones will boot up presenting the Voice Services screen
In order to boot up to this point the phone still requires it's own IP, whether it's using DHCP or hardcoding an IP Address.
Resolution
In order to toggle between the 2 Voice Service Screens
Phone first will appear with the following screen:
Initial screen
Press the "up" direction on the navigation cluster or
Use the touch screen on the 6940 and Press Service Type
Now press the right arrow softkey which toggles the screen to the MiVoice Border Gateway Screen
Press the "down" direction on the navigation cluster will allow you to enter the IP of the MiVoice Border Gateway Server or
Touch the IP address box on the 6940 and enter the IP of the MiVoice Border Gateway
Press save and restart the phone.
Additional Notes
Additional Notes
Note once the phone connects to the TFTP server of the Controller/Mivoice Border Gateway it will download whatever firmware is installed.
Refer to the appropriate Installation guide to set up appropriate options (DHCP/MDNS) for phones connecting to On Premise Controllers.
(MiVoice Business , MiVoice MX-One, MiVoice 250, MiVoice 400, MiVoice 5000)