Dial pattern problem

Using sipstation on freepbx, I cannot dial 1 before a 10 digit number (I get all circuits are busy message). Some numbers called when enter as 10 digit numbers a 1 is being prepended to the number in the phone history, so a redial won’t work. How can I test for a 1 and strip it or get the system to accept a 1 in the beginning of a number?

https://wiki.freepbx.org/display/FPG/Outbound+Routes+Module

https://wiki.freepbx.org/display/FPG/Outbound+Routes+Module+User+Guide

https://wiki.freepbx.org/display/FPG/Outbound+Routes+Configuration+Examples