[Drupal] ReCaptcha does not work on Login/Register page. Error 400 (Bad request)

Hi all Some problem with reCaptcha on Druapl 7 project. After user open "Login" or "Register new aaccount" page and than click on "I`m not a orbot" on console appear error: "400 (Bad request)"; http://bit.ly/1BPlpeU After I clear cache, reCapthca work correctly. What happend with API2. -- You received this message because you are subscribed to the Google Groups "reCAPTCHA" group. To unsubscribe from this group and stop receiving emails from it, send an email to recaptcha+unsubscribe@googlegroups.com. To post to this group, send email to recaptcha@googlegroups.com. Visit this group at http://bit.ly/1dkFnYd. For more options, visit http://bit.ly/P65DvS.