Why doesn't Liability Automatic Offsets work with Payables Mapping Set and Subledger Account Rule?

Summary: Set up Payables Subledger Accounting rules to map a few of the Primary Balancing Segments to new ones created. Expense side works but not the Liabiity Automatic offset.

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Created Mapping Set (For 5 segments only to be mapped) for Primary Balancing Segment (PBS) for Invoice Distribution Account Source. Created an Account Rule. Added to SL JE Rule Set & Accounting Method. Segments in Mapping set are correct including liability PBS, but for all other PBS the liability defaults to the system default instead of using the Automatic Offset of Primary Balancing Segment.

Current set up for the Auto Offset has "Copy" as the Segment Rule. I created a mapping set for the Journal Line rule for Liability but that doesn't work either.