Subform only works the first time

[bevpro]

I have a form with a subform off of a tab. When I add a new record to the form, then click on the subform, a field is populated with the linked field from the main form. This works great. Then I go back to the main form and add another record. This time when I go to the subform, the field is NOT populated. It is as if the record from the main form was not inserted into the database yet. It works great on the first record but does not work for subsequent records.