Can't update profile

I have tried to update my profile fields (like email address - it is out-of-date), but after several attempts with various browsers, it always comes back to the original settings.

When I edit the fields I am at this URL:

https://mibuso.com/account/user-profile

And when I click save the fields revert back to the original values and the URL shows:

https://mibuso.com/account/user-profile?recaptcha-failed

I'm stumped.

Thanks for any suggestions!