Facebook actually checks the Privacy Policy page and attempts to determine if it's a valid privacy policy. Is the URL you linked to a real Privacy Policy page, or is it just any page on your site?
If you don't have one, we'd recommend checking out
www.generateprivacypolicy.com/ which can make a privacy policy for your site that should work with Facebook.
If you do have one, can you link, or private message, me the link of your privacy policy that you're using. We'll gladly take a look and help how we can.
I hope that helps,
Alex