Documents can be uploaded when you challenge a case.
In the top right corner of the Case Details page, click the “Take Action” button.
From the dropdown, select “Challenge”
Drag and drop your files into the upload box, or use the “Browse Computer” link to select them from your hard drive.
After the file has uploaded, click the “Next” button on the bottom right of the panel.
Add comments if desired.
Submit your challenge for review.