Clicking magic link using email sign-in returns DEPLOYMENT_NOT_FOUND

[christopher-ha]

I only recently got this error when I deployed to Vercel. It worked before when I was doing it on localhost, but now even trying the sign-in flow on localhost doesn't work.

All of the magic links I've been using for the past month have been the same. I've tried setting my NEXTAUTH_URL env to my domain, the vercel domain, and completely removing it. Nothing has worked.

I think it might have to do with the "url2810" in the subdomain of the magic login link? Does vercel think that it's a website? I'm not sure.

Same URL that has worked previously:

Error message after clicking magic link sign-in URL:

Next-auth 4.10.3
Next.js 12.2.2

[christopher-ha]

Solution:

The error was caused by SendGrid's subdomain not being configured in the DNS settings of the Vercel project.
Everything now works as intended.