Head to your Credentials tab.

Scroll down to the Health Documents section. Find the Health Document you'd like to edit, delete, or update then click the Update button to update an existing health document.

The drawer to make your changes will slide out from the right where you can edit as needed:
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When you are done editing, don't forget to Save! To cancel any changes you've made, simply click the left arrow in the top bar to close the editing panel.
​Your changes will not be saved unless you've pressed "Save" before exiting!