Populating subforms with Provider ID

I'm attempting to link two sub forms together using the Provider ID and the SubPageLink set up as such..
No.=FIELD(No.),Document Line No.=FIELD(Document Line No.),Line No.=FIELD(Line No.),Label No.=FIELD(Label No.),Pack Qty.=FIELD(Pack Qty.).

When I look at these subforms certain fields are populating correctly such as the No., Line No. however the others arent, such as Pack Qty.


Any ideas why the other fields won't populate the same?