Production getting NO_SECRET even after adding 'secret: <NEXTAUTH_SECRET>' to [...nextAuth].js

[RodRitter]

Hey all, I wanted to post this as a bug but it's my company's app, so I thought I'd open a discussion so I don't have to disclose any private info.

Locally, everything works fine. When we went onto production, it started giving NO_SECRET errors.

I've followed the docs and searched & implemented other solutions people have posted but haven't had any success.

next.config.js

const nextConfig = {
    {...},
    serverRuntimeConfig: {
        {...},
        NEXTAUTH_SECRET: process.env.NEXTAUTH_SECRET
    }
}

[...nextAuth].js

import NextAuth from 'next-auth';
import DuendeIDS6Provider from 'next-auth/providers/duende-identity-server6';
import getConfig from 'next/config';

const { serverRuntimeConfig } = getConfig();

export default NextAuth({
    session: {
        strategy: 'jwt',
     },
    providers: [...],
    callbacks: [...],
    pages: [...].
    secret: serverRuntimeConfig.NEXTAUTH_SECRET,
});

Server Log

https://next-auth.js.org/errors#no_secret Please define a `secret` in production. MissingSecret [MissingSecretError]: Please define a `secret` in production.

Can anyone think of anything else I'm missing here?