V3 does not display

I have successfully used the plugin with Capcha V2. However last week I had a load of spam registrations on the site, so it seems not to be stopping bots.

I decided to try V3. However this doesn’t work at all. The Capcha does not display and I can register an account without having to prove I’m not a bot.

Can you suggest what may have gone wrong?

If you’d like a link to the site, please indicate how I should send it to you privately.