Duplicate “Passwords” app. How do I deal with the ones I don’t need?

Somehow 3 app icons have appeared (each on a different page of the iPad.) A casual inspection leads me to believe they are identical. Same numbers of passwords in different groups, but without opening each and comparing site by site I’m not sure and have not deleted anything.

Two questions:

• How did this happen?
• Is there an automated way to compare all three?