Custom domains 404 despite correct DNS & healthy build

Hi everyone,

I’m running into a strange issue where both my apex domain and www subdomain return a 404, even though everything on my end is configured correctly:

  1. DNS (managed at Namecheap)
  • @ A → 76.76.21.21 & 76.76.21.93
  • www CNAME → cname.vercel-dns.com
  1. Vercel Project Settings
  • Under Domains, I have densitycalc.ai → Production and www.densitycalc.ai → Production (no redirects).
  • I removed all leftover .vercel.app aliases.
  • I turned off Deployment Protection so the site is fully public.
  1. Deployments
  • My latest build at / generates correctly and returns HTTP/2 200 OK when I curl the official .vercel.app URL after disabling SSO.
  • I have redeployed and promoted multiple times.
  1. Symptoms
  • curl -I https://densitycalc.vercel.app → 404 DEPLOYMENT_NOT_FOUND
  • curl -I https://densitycalc.ai → 404 NOT_FOUND
  • curl -I https://www.densitycalc.ai → 404 NOT_FOUND

Everything points at a stuck or corrupted alias/routing cache on the Vercel edge. Could a member of the Vercel team please flush my project’s alias mappings or investigate the edge‐routing table for densitycalc? Thank you!

There’s another community post with 404 debugging tips that might be helpful. Please give these solutions a try and let us know how it goes.

A human should be around soon to offer more advice. But you can also get helpful information quickly by asking v0.