Access blocked: WordPress’s request does not comply with Google’s policies

I clicked on a FB add to have WordPress.com build a site for me, but I got this message when I tried to log in using my gmail account:

Access blocked: WordPress’s request does not comply with Google’s policies

WordPress’s request does not comply with Google’s” Use secure browsers” policy. If this app has a website, you can open a web browser and try signing in from there. If you are attempting to access a wireless network, please follow these instructions.

You can also contact the developer to let them know their app must comply with Google’s “Use secure browsers” policy.

Learn more about this error

If you are a developer of WordPress, see error details.

Error 403: disallowed_useragent