Now to upgrade a project, the original is made of access2002 form program, to upgrade to the access2019,
Problem is: after the upgrade, main form starts, the child form the data load: no, no, according to feel not execute child form data source,

Upgrade before the child form code:
Data source specifies a stored procedure nsp_ unit price said
Parameters have a: @ item=FORMS! [FM_ item price] [object]

After the upgrade code:
The main forms of data sources is given form name:
FMS_ unit price saidChild form data source: the exec nsp_ said the unit price @ items=' '