Trouble changing avatar after initial upload

Hello!
I’m testing this plugin and have run into an issue:

-On the front end I can initially click Choose File and change the user avatar (to “1st image”).
-But when I try to change it again, the 2nd image I select will not show up. It remains the 1st image. (I don’t have caching on this site and I’m testing in an incognito window.)
-When I go to the backend I can see that the 2nd image is in the user profile. And from there I can add a completely new image that shows up on the front end.
-But when I then go back to the front end and try again to update to a different image, it changes it back to the “1st image”!

Any suggestions for what may be going on? I’d love to use this plugin but I want users to be able to update their own avatar and it seems that this scenario would be confusing. Thanks!