When in the Photoshop Elements 2021 Editor, a popup stating that :
"You have a new update!"
This is an update for Photoshop Elements:
with an Install Now or Install upon exit. Unfortunately the install stops at 6% stating that there is an Update Conflict.
Please save your work and close the following programs for all logged in users, then click "Continue"
Adobe Photoshop Elements 2021
(Error Code 131)
Some people over in the Premiere Elements forum had similar problems
What worked for many of them was to download the current trial, which will/should have the update, and then enter your serial number to convert the trial to a registered program
[Moderator moved to Photoshop Elements.]
Have you tried closing Adobe Photoshop Elements 2021 and then clicking on continue.
If for some reason you are unable to find the application Adobe Photoshop Elements 2021 running on your system, you can follow the steps listed at this page to close the application.
Hope this helps resolve your query.