Intermediary page being show in production mode

[DanielAtCosmicDNA]

Environment

System:
OS: Linux 5.15 Debian GNU/Linux 12 (bookworm) 12 (bookworm)
CPU: (8) x64 Intel(R) Xeon(R) CPU E3-1505M v5 @ 2.80GHz
Memory: 10.25 GB / 15.53 GB
Container: Yes
Shell: 5.9 - /usr/bin/zsh
Binaries:
Node: 20.14.0 - ~/.nvm/versions/node/v20.14.0/bin/node
Yarn: 1.22.22 - /usr/bin/yarn
npm: 10.7.0 - ~/.nvm/versions/node/v20.14.0/bin/npm
pnpm: 9.1.4 - ~/.local/share/pnpm/pnpm
Browsers:
Chromium: 125.0.6422.141
npmPackages:
next: 14.2.3 => 14.2.3
next-auth: ^4.24.7 => 4.24.7
react: ^18 => 18.3.1

Reproduction URL

https://github.com/DanielAtCosmicDNA/next-auth-dev

Describe the issue

When running with yarn dev, Oauth login works perfectly fine. But when running in production with yarn build && yarn start, an intermediary page is rendered upon login.

How to reproduce

Copy .env.example to .env, set the environment variables for GitHub and Google providers, and a NEXTAUTH_SECRET. Additionally set a mongodb database URL.

run "yarn build && yarn start"

open localhost:3000, click on GitHub oauth login.
Observe the intermediary page in between.

Expected behavior

In production it should work the same way it works when running as yarn dev without any intermediary page. Here is the intermediary page and which should not be there:

[Ali-Raza764]

Try setting custom signin pages in your auth/[...nextauth] route If user is logged out it should use the custom signin page. From there if the error persists it would be clear it is realted to the session or the middleware
Refrence Docs

[DanielAtCosmicDNA]

@Ali-Raza764, It is set right here: https://github.com/DanielAtCosmicDNA/next-auth-dev/blob/main/middleware.js#L5.
If I add the following to authOptions at auth/[...nextauth], the behaviour does not change.

  pages: {
    signIn: '/'
  }