Cannot create PR: linked GitHub account is reported as no longer available

Short summary

The GitHub Copilot App consistently fails to create a pull request because it reports that the project's GitHub account is no longer available, even though project settings correctly show the account as linked.

Affected version or release

The issue started occurring recently and persists after updating the app. Exact affected version not recorded.

Installation context

GitHub Copilot App on Windows. The failure occurs when creating a PR from a project session and also persists in a newly started session.

What happened?

Every attempt to create a pull request fails with this error in the Create pull request section:

This project's GitHub account is no longer available. Please re-link the project to a GitHub account before creating a pull request.

However, opening the project's settings and toggling the GitHub account correctly shows that my account is linked. PR creation still fails afterward.

Steps to reproduce

1. Open an affected project in the GitHub Copilot App.
2. Open the project settings and toggle the GitHub account; confirm that the account is shown as linked.
3. Return to the session and attempt to create a pull request.
4. Observe the error above, despite the account being shown as linked in settings.
5. Restart the app or start a new session and retry; the same failure persists.

Expected behavior

When the project's GitHub account is linked, the app should use that account to create the pull request rather than report that the account is unavailable. Project settings and PR creation should agree on whether the account is linked.

Additional context

The following troubleshooting has not resolved the issue:

• Updating the app.
• Restarting the app.
• Starting a new session.
• Toggling the account in project settings and confirming it is shown as linked.

This blocks PR creation from the app. The error above was transcribed from a screenshot of the failure.

Start with the GitHub Copilot App's Create pull request flow on Windows and compare its account-availability check with the linked-account state shown in project settings. Reproduce the failure using the listed steps, including restarting the app and starting a new session; done means a linked account is accepted and pull request creation no longer reports it as unavailable.