pre-existing subdirectory install failed

I set up a WordPress site for a client in a subdirectoy–something I have done several times before with other client sites and those all worked fine.
Theme: Avada

Site URL: https://laportepeinte.com/ (there is a temp HTML page showing now but it looked the same as the page in the subdirectory link below)
Subdirectory: https://laportepeinte.com/studiofolio/

I followed these instructions: https://codex.www.ads-software.com/Giving_WordPress_Its_Own_Directory#Using_a_pre-existing_subdirectory_install

But it’s not working. I’m worried changing the URL Settings in the Dashboard didn’t ‘take’ or I forgot to hit ‘save’?

I cannot access the admin either:
https://laportepeinte.com/studiofolio/wp-admin

Help! Not sure what to do. I exported the database & downloaded all the files via FTP. Is there something in one of the PHP files I can change to fix this?

Thanks!