DejaDup now fails to back up

DejaDup worked fine. I back up to an external HD.

Now DejaDup requests an encryption password and then seemingly nothing happens. In the past it showed a rectangle and started the back up until it requested a password to test. These day after nothing has happened it again requests the password but in has been filled in and put into a blue rectangles. Clicking ci=ontinue repeats the process and no back up is made.

Please tell me where I fell off the apple cart and please help me onto it again.

Thank you for your attention.
James Gibbens