Confirm button partially off screen when trying to download app

When I go to download apps on my iPad Pro (11-inch) a screen comes up asking me to “confirm with button”, or something like that, and a button appears in the upper left part of the screen that is moving back and forth and says “double click.”  The problem is that 90% of the button is off the screen so I can’t click on it, so I can’t download the app.  I’ve never seen this new screen with this prompt until last week, but it won’t let me download these apps.  This screen is coming up on my iPhone and iPad.  I’ve turned my devices off and on in the hope that it would fix the problem but it doesn’t.  How do I fix this?