Change gmail id for captcha

As long as you have access to the website files, all you need to do is create the appropriate API keys with your new gmail/recaptcha account and change them in the website code.

If I create new Gmail id & new reCaptcha and use the new reCaptcha then what will be happened of old reCaptcha.
If I use new reCaptcha then will it create any technical problem in future ?

My official answer is "probably not" (technical problems).  It should be simply editing the API keys in the website files where appropriate. 

The old recaptcha will stop being used.

@enlivenapp
Thanks a lot for your valuable suggestion.