Hi Sabina
This did the trick. Any idea why this was broken?
Currently I have made a new V3 Recaptcha key and it seems the problem is gone for the moment. Seems there was something wrong with either the integration after update to the new version or the amount of spam blocking the recaptcha from working correctly.
The form info is saved in Contact Form DB 7 plugin, but no e-mail was sent out. (And again, the form gives the error: “Something went wrong” back to the user.