You can reprint a shipping label up to 24 hours from the initial printing.
To reprint a label that you just printed:
To reprint a label from the History screen:
The number of times you can reprint varies by carrier:
Tip: If you save a PDF of the label to your computer when you first print, you can reprint it later from the PDF file. This is useful if the 24 hour reprint period has elapsed.
UPDATED: April 19, 2021