I have the same problem on osclass 3.02. reCAPTCHA v1 is working fine on all pages, V2 is working fine on all pages, except register page. I get the error "The reCAPTCHA was not entered correctly" I think it is related to the method the v2 uses to verify the answer from google api. I have tried modifying the user actions file, the recaptcha lib file and I made V2 work but it did not work on register page. Is there a tutorial how to migrate v1 to v2?
Regards!