My custom domain intermittently returns 503 with the TLS handshake presenting no certificate, from multiple external locations (server checks from a different region, my browser, Googlebot's crawl). Meanwhile Vercel's own diagnostic returns 200 with a valid Let's Encrypt cert (expires 2026-10-10). Setup: registrar/NS/DNS(A·ALIAS·CAA) all Vercel-managed; dashboard shows "Valid Configuration / Production"; the .vercel.app domain works fine. It briefly worked (Google indexed the homepage) then dropped after a redeploy, and drops again on each deploy. Remove+re-add and Refresh only fix it temporarily. Looks like a regional edge-propagation / cert-binding issue — cert valid but not served uniformly across edge PoPs, and not persisting through deployments. Can someone from Vercel investigate?