How to Uninstall and Reinstall the App (Windows)
Edited
To uninstall the app:
Select Start, then select Settings → Apps → Apps & features.
Select the app you want to remove (Fathom), and then select Uninstall.
!https://i.imgur.com/kbsUieA.gif
To install the app:
You can download the Windows Desktop App by clicking: HERE!
See more information about uninstalling or removing apps and programs in Windows