Site is up, but the homepage is a 404. Here's why that happens.
Hey — this is almost always the same thing: your build process wipes and recreates the deploy folder, and index.html didn't get copied in this time. Maybe a promote list changed, maybe a build script was edited, maybe something overwrote it with a stub. The result is the same — no homepage on the live server.
ls _site/index.html
If that file isn't there after a local build, the homepage was never going to deploy. That's your answer.
Find the last time the homepage was correct:
git log --oneline -- index.html | head -5
Pull it back:
git checkout [commit] -- index.html && git commit -m "restore: homepage" && git push
Deploy takes 3–5 minutes. Check in incognito when it's done.
One line at the top of your build script (after mkdir -p _site) locks the homepage in permanently:
[ -f index.html ] && cp index.html _site/index.html