Grandstream DP720 - no incoming calls on 2nd extension

I got my hands on the new released Grandstream DP720, impressive phone for anyone looking for sip dect cordless option. Even got 75 yards (literally) away from the base with a crystal clear call, great phone…

PBX version: 10.13.66-11
Asterisk Version: 13.7.1

Now to the point, since this phone just released End Point does not have it loaded, but the Dp715 template does a pretty good job. My first extension can make and receive calls, no issues, perfectly setup…
The 2nd extension provisioned under the same MAC, its unique extension number (different from the 1st phone) and listed as “Account 2” can receive calls from the outside and from other extensions. Although, it cannot make outbound calls or call other extensions. When making a call from the 2nd extension I get only a busy sound.

My settings are the same for both handsets. Even on the Grandstream portal side I have tried listing them both under the same profile and separate profiles, makes no difference.

Both extensions are Chan_Sip loads. Any thoughts or suggestions?

Issue is fixed and I now have three (3) DP720 phones running on Freepbx. The issue was in the Grandstream portal, changed sip setting of “outgoing calls without registration = Yes”. I also have all three phones provisioned on Chan_PJSip, each phone assigned to its own account (account 1, account 2, account 3).