When a database field is added to a report, a text field is added to the report header as its associated header. If you move or resize the database field, the changes are reflexed in the header.
Occassionally, this linkage will break. Is there a way to reconnect the link?
The default setting … unless you change it in Options … is to add the name of the field into the Page Header if you add a field into the Details section.
If you “lose” the column label in the Page Header, most people just delete the field and add it back into the Details section.
Additionally, if you ever want to add a field without getting the automatic label in the Page Header, first drop it into a section other than the Details section … then move it into the Detail section.