Google Recaptcha v2 verification failed

[balajivinnakota]

Dear GIT,

I'm completely new to this repository.. Kindly understand my problem. I have faced one issue with recaptcha v2. I completed my code with validations on client and server side. But interesting one i have noticed in this recaptcha v2 is. if i'm a guest authenticating my login page(demo) with out login of any other google account in another tab, it is showing number(image) to enter(type) and validate. if i'm a guest authenticating my login page(demo) with login into one of my google account in another tab, it is not showing any captcha and validating "i'm not a robot!".. Can anybody tell me whats going on???