it's not solved i missclicked

This is most likely still a GitHub App installation or source-binding problem, even if you already disconnected and reconnected once.

The key errors are:

Bad credentials

Failed to fetch repository files

There was an error deploying from source

That means Railway is failing before it can read the repo contents. I would check it in this order:

1. Open GitHub.
2. Go to Settings -> Applications -> Installed GitHub Apps.
3. Open the Railway app installation.
4. If it is set to selected repositories, make sure this exact private repo is selected.
5. Save the GitHub App installation.

If the repo is under a GitHub organization, also check org SSO or third-party app restrictions. Some orgs let you install the app but still block access until SSO is approved for that app.

Then reconnect the Railway source from the service, not only from account settings:

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

Railway service -> Settings -> Source -> connect GitHub source again

Select the private repo and branch again

Trigger a fresh deploy

Also verify the repo has not been renamed, transferred to another owner, archived, or made inaccessible to the GitHub user that installed the Railway app. Railway access is tied to the GitHub App installation and repository permission, not just to whether your Railway account is logged in.

One quick isolate test is to create a temporary new Railway service and try to deploy from the same private repo:

If the new service also cannot fetch files, the GitHub App installation or org access is still wrong.

If the new service can fetch files, the original Railway service likely has a stale source binding, and reconnecting the service source should fix it.

I would not spend time changing build commands, environment variables, or Docker/Nixpacks settings yet. The failure is happening at source fetch time, before Railway reaches the build step.

Hi there! GitHub is currently experiencing an issue with app installation token authentication which is causing these errors. You can track it here: https://www.githubstatus.com/incidents/k5z4d1v1tqmt. No action needed on your end, deploys should recover once GitHub resolves this. Apologies for the trouble!