Tool to indicate wrong settings

Hi all,
I tried searching but did not find something that can help.
I am wondering is there some tool that can help me to indicate wrong settings while working with FreePBX.
I set the inbound routs and all what needed according to manuals, but when the call comes in all I can hear is “This number is not in service” message.
Thanks in advance

P.S. In CDRs i see that call came into the system.

If you watch the call in the asterisk CLI (asterisk -rvv) you will see what its doing. Perhaps your inbound route is too specific. Wrong DID maybe.