How to setup an env on AWS Elastic Beanstalk when JWT appears to be wrong?

[thetaPC]

Hello!

I have successfully deployed a Next.js with Next-Auth project on AWS EB. Everything looks fine. However, I can't get passed the sign in form.

There aren't many errors to go off in my opinion.

Here's what the browser console shows:
502 Bad Gateway: POST http://----.elasticbeanstalk.com/api/auth/callback/credentials?
Uncaught (in promise) SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data

Here's what the EB logs show:
upstream sent too big header while reading response header from upstream, client: x.x.x.x, server: , request: "POST /api/auth/callback/credentials? HTTP/1.1", upstream: "http://-----/api/auth/callback/credentials?", host: "----", referrer: "http://----.elasticbeanstalk.com/"

I've also shoved some console logs in [...nextauth].tsx file to find the issue.

• The console logs show fine all through the Providers.Credentials.
• The console logs show fine all through the jwt callbacks.
• But the console logs never appear in the session callback.
  So it dies somewhere between jwt and session callback.