If you don't normally press "1" before dialing a 10 digit number, try doing it for the one that won't work. The first two digits in the area code you are trying to call may conflict with a feature code in the PBX. If that doesn't work, the number you are dialing may have been added to the PBX DNC (do not call) list and would need to be removed by the system administrator.
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If you don't normally press "1" before dialing a 10 digit number, try doing it for the one that won't work. The first two digits in the area code you are trying to call may conflict with a feature code in the PBX. If that doesn't work, the number you are dialing may have been added to the PBX DNC (do not call) list and would need to be removed by the system administrator.