reCaptcha v3

I activated the reCaptcha v3 from Google. I can now see their logo on our page as well..
However, when a user fill s out a form now, it is showing an error:

There was an error trying to send your message. Please try again later.

Moment, I remove the reCaptcha, it becomes ok again. Pls advise.

The page I need help with: [log in to see the link]