Probably I posted it in the wrong Forum, I'm sorry for that. I kindly ask for an answer.
I added "I'm not a robot" to my login page (sepforum.sep.org.gr). How can I deactivate "Show your human side" from the login page (Σύνδεση – Forum Σώματος Ελλήνων Προσκόπων (sep.org.gr)?
First of all thank you for your quick answer. I don't really Know which plugin is the one that triggers that. My installed plugins are :
Akismet Anti-Spam, AMP, Crowdsignal Forms, Crowdsignal Polls & Ratings, Gutenberg, Jetpack, Layout Grid, Page Optimize, Post SMTP, WordPress.com Editing Toolkit, wpForo
Sorry for the list but I don't really know if someone of these causes the problems.
Sorry to say but after deactivating almost every plugin no change, unfortunately.