In addition to selecting the correct printer and page size on the Print window, the Asset Tag Label report must be edited to reflect the shorter label height:

Under Reports > All Reports > Labels, select the Asset Tag Label and click Design Report.

When the Report Designer tab first opens, the Properties window on the left should display the Page Size as Page Width 2, Page Height 1. Change the Height to 0.75.

In the report design area, click on the light blue background so it selects the whole background, not one of the data objects. On the left, expand Position, and change the Height there to 0.75.

Click on the individual objects to select them so you can reduce their height by dragging the small squares surrounding the selected object, then reposition them to fit within the blue background by dragging the objects themselves. If desired, you can remove the Description object above the barcode and/or the human readable Asset Tag object below the barcode.