This looks like a GitHub App authorization problem and not a branch problem.

The important clue is:

[ERROR] ##NOT-AUTHORIZED## repository not authorized

Because the repo is private, Railway has to be authorized for that exact repository. Re-authenticating your Railway login can still leave the GitHub App installation without access to the private repo.

Check the GitHub installation first:

GitHub -> Settings -> Applications -> Installed GitHub Apps -> Railway -> Configure

Then verify that SymbioticSystems/bitebuddy-backend is included in the Railway installation. If the installation is set to selected repositories, add that repo and save.

If the repo belongs to an organization, also check whether the organization requires SSO approval for the Railway app. In that case, authorize Railway for the org as well.

After that, reconnect the service source in Railway:

Railway service -> Settings -> Source -> disconnect/reconnect GitHub source

Then choose the repo and branch again and trigger a new deployment.

I would not change build settings, environment variables, or branch names yet. The error is happening before Railway can read the repository properly.

If the branch list still does not load, do a clean source reconnect:

1. Remove the GitHub source from the Railway service.
2. In GitHub, configure or reinstall the Railway GitHub App for this exact repo.
3. Return to Railway and connect the service source again.
4. Select the branch again.

Also check whether the repo was renamed, transferred, archived, or moved under a different GitHub account or organization. A previous deploy succeeding two hours ago does not rule this out, because GitHub App repository access can change independently of the last successful deployment.

The quick test is to create a temporary new Railway service and try Deploy from GitHub repo with the same private repo. If that new service also cannot see the branches, the issue is GitHub/Railway App repository access. If the new service can see the branches, the existing service has a stale source binding and reconnecting the source should fix it.