kindle app: Cannot get to the library main menu

On my new iPad Air, I cannot get to the library main menu in the kindle app. No amount of tapping on the screen will bring up the main menu. I can flip through the book with no issues, but can't get back to the main menu to get to another book or the table of content, etc.

I see a similar question was asked a few years ago, with over 300 people indicating they are having the same issue, but no resolution. Any help appreciated.