Custom Form – slug

Hi there, I’ve updated to version 1.7 and the following code stopped working

apply_filters( ‘gglcptch_display_recaptcha’, ”);

I read the instruction here to update the code https://support.bestwebsoft.com/hc/en-us/articles/202352499-How-to-add-reCaptcha-plugin-to-a-custom-form-on-my-WordPress-website-

but couldn’t get it to work.

I tried adding

apply_filters( ‘gglcptch_display_recaptcha’, ”, ‘register’ );

‘register’ is the page slug where my custom user registration form is located e.g. https://<domain>/register/

Can you please advise what the slug should be for the filter?

Thanks!

Sandy