404 Errors

I use this plugin on one of my sites: https://laurawrites.net, and it runs just fine.

I tried to install it on another site today and can’t get anything to show. It gives me a 404 error on all my pages. This is supposed to be where my faq starts: https://vacreeper.com/hrf_faq/virginia-creeper-faq/

Any help will be most appreciated.