Invalid site key

Same here!
This is message i get ERROR for site owner: Invalid site key

I got the solution.
In your reCAPTCHA admin panel;
go to Settings, scroll down to security preference and keep the cursor low (easiest to users) and disable the check box of ‘Verify the origin of reCAPTCHA…’

Now It will work

@vismithams I tried that but it didn’t work. Site is using Cloudflare though. Would that have some sort of effect on it?

No. it wont.
try to change the url formats. e.g https://, www, xx.com etc

I figured out a better way, easier way. CF7 has built in integration now. Was brilliant! No need for this plugin now.

can you share?

Certainly. Goto CF7 inside your backend. Click Contact > Integration then add your keys right there. Done.

Latest CF7 does not use V2 but instructions are there for those wanting to use it.

Read Instructions

thanks