Why the missing action error when incoming from GoIP to FreePBX?

Question

Asterisk

I set up FreePBX and GoIP according to the article: https://habr.com/ru/post/464765
Registration of the trunk with GoIP was successful.
However, with an incoming call from GoIP to PBX, no matter what number I transmit, no matter what settings I enter, the output is still an error:
[2021-06-23 16:50:46] NOTICE[20121][C-00000040]: chan_sip.c:26447 handle_request_invite: Call from '9787487341' (192.168.1.42:5060) to extension '1' rejected because extension not found in context 'from-trunk-sip-9787487341-custom'.

Here are the extension settings for this trunk (extensions_additional.conf):
[from-trunk-sip-9787487341]
include => from-trunk-sip-9787487341-custom
exten => _.,1,Set(GROUP()=OUT_4)
exten => _.,n,Goto(from-trunk,${EXTEN},1)

As I understand "_." - this means all the numbers, where does this error come from?
The GoIP and FreePBX settings correspond to those in the article, adjusted for my numbers and passwords.

Answer 1

I figured it out myself, but rather intuitively.
How does it work, I do not understand!
So all I had to do was remove "-custom" from the line "context=from-trunk-sip-9651234567-custom"
How did I get there? Quite simply, all other trunks did not have this postscript at the end, but appeared with it in the extensions_additional.conf file automatically. I logically concluded that this was some kind of technical postscript set automatically, and removed it, as soon as I did it, everything worked.
Ps: I’ll note one detail, I don’t just have FreePBX, but a modified paid FreePBX called MetPBX, from Postmet.de