Form Builder not working

Hi,

I’m trying to change the register form. When I first installed this – I could remove the First and Last name fields on this form. However, these were not removed in the final page.

Weirdly, I went back into the form builder and now I cannot “expand and view field related settings” and thus remove these fields. I even uninstalled and re-installed the plugin. Same issue. Could you please advise?