Allow from own SIPTRUNK

Hello!

I need to do somthing like this:

I have SIP TRUNK from my operator with 100 DDI.

I must create own sip trunk to give it to other ASTERISK (this is simple) but this ASTERISK have 10 others users (DDI).

When I connect to my FREEPBX using register user (whati own created) everything is ok, but when I wont to connect by other user I got UNAUTHORIZED.

ex.
REGISTERED_USER0@my_domain -> everything isgreat
USER1@my_domain -> I have UNATHORIZED

Please help how to do this thing to give this ASTERISK accept to use range of users (DDI) or no limit users (uutbound route will make rest)???

I can’t use in this ASTERISK any change like REMOTE-PARTY becouse this is close dialling system, using only CALLERID like I write before.

Best regards!