When I print labels (2 rows of 7 = 14 labels in total per sheet), the name and address that comes after the name and address at the bottom of the first column drops off, and the name and address that comes after the name and address at the bottom of the second column drops off. I would be grateful if somebody could explain to me why?

If it's just the bottom row of labels that gets cut off, try reducing the size of the Footer. It could also be something with the margins for the particular printer you are using, or that your Page Setup does not have the correct paper size selected.

If you're really stuck, try recreating your labels by using the New Layout/report wizard. Select Labels as the type of layout, then select the label model. FileMaker does a pretty good job sizing parts so they fit for the selected label model.