I’m experiencing the same situation. The reCAPTCHA box shows it’s verified, but then submitting the form shows “CATPCHA failed” as part of the gravity forms notification (just like in your screenshot). Also, this started happening after moving the site from one server to another (domain stayed the same).
I uninstalled & reinstalled the plugin, checked the database for instances of the server-level file/folder path being saved (which would then need to be updated), checked the plugin folder for similar instances of the server’s file/folder path being saved, removed & re-added the field to the form… none of it worked. I also tried to make it so it wouldn’t use HTTPS for items since my site’s using HTTP, but that didn’t result in a fix either.
I then switched to Gravity Forms’ built-in CATPCHA field (providing the same exact reCATPCHA keys in the GF settings), and that worked no problem. Unfortunately, I’m going to have to call that good for now, and I was unable to find the real cause of the issue or the fix.
Is there some sort of server technology that would need to be enabled/configured that would cause this No CAPTCHA plugin to not work while the built-in reCAPTCHA works just fine? Or did it actually break from the act of moving the site somehow? I’m not sure, but an update would be greatly appreciated.