AX / Dynamics 365 For Finance and Operations blog

When we open the child form from another form the datasource of the child form is sync with the previous form this is due to the dynalink between these two forms and all the data is shown on the child form.

you can use the below code on the init method of the child form after the super() to remove the dynalink between these two forms.

SalesTable_ds.queryBuildDataSource().clearDynalinks();