I got "Your call cannot be completed..." when dial any extension start with '10' or '11'

I have been using FreePBX for a long time and all office extensions configured with “11x” or “10x” have been working fine on all SIP phones. Recently we got this msg error: “Your call can not be completed at this dial…”. on some phones when we dialed or transferred the call to these extensions, but it did work in some other phones. Reboot the trouble phones does not help.

I couldn’t find any documents related to this. Can someone help me?
Thanks very much.

You are running a very old version of FreePBX that is out of official support. The supported versions of FreePBX are 2.6 and 2.7.

You need to enable debugging at the Asterisk CLI, then look at the log files to be able to determine the error you are getting.