Are you sure you’re not confusing analogue/POTS line ports with analogue ‘telephone’ extension ports? E.g. If you have two combo cards in the system you only have 8 analogue line ports (ports 9-12) ports 7-8 are analogue extension ports for fax machines, cordless phones, etc.
Also if you’ve changed the Line Group numbers make sure that’s consistent with the ARS table for outgoing calls (if using) and the ICR table.
Thanks, Tim
Adelaide, Australia