EOS Auth Error: Deployment User Access Forbidden

We get an errors.com.epicgames.eos.auth.deployment_user_access_forbidden error for a user in our game. The same user didn’t have any problem before, but he gets this error now and can’t log in to the game.

Why would that be? Does anyone know anything about it? I couldn’t find any information online about this. This is not even in the SDK Error Codes list

Note: We have +20 testers but only one person got this error and that person was ok before.

For anyone who faces with this problem: It is because the user has no access to the Deployment ID you are using. We were using Test Deployment ID (which uses Dev Sandbox), so people who don’t have Dev access are faced with this. If you use the Release Deployment ID, everyone can access it.

Release: Everyone
Live: Live + Stage + Dev
Stage: Stage + Dev
Test & Dev: Dev