Thank you, mc2021, and Newdude, for replying.
I clicked on the link you sent me, and came to the screen shown in the 1st attached screenshot. It shows buttons for downloading and installing the app. I clicked on the button for Google Play. Then the screen shown in the 2nd attached screen shot was displayed. It shows a button that says "Open", which means that I already have the app installed. When I push the button, I am returned to the screen shown in the screenshot in my original post.
What am I doing wrong?
Thank you.