[BUG] All Authentication Methods Fail (fetch failed) on Production Deployment

[Khushi1310-nayak]

🐛 Bug Description

Authentication is completely non-functional on the production deployment. All available authentication methods fail, including Email Sign Up, Email Login, Google OAuth, GitHub OAuth, Demo Credentials, and Magic Link.

A red "fetch failed" error is displayed on both the Sign Up and Login pages, indicating that the frontend is unable to communicate with the authentication service or backend API.

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Steps to Reproduce

1. Open the production deployment.
2. Navigate to Sign Up (/auth/signup).
3. Enter a valid Full Name, Email, Password, and Confirm Password.
4. Click Create Account.
5. Observe the "fetch failed" error.

Additionally:

1. Navigate to Login (/auth/login).
2. Click Continue with Google.
3. Click Continue with GitHub.
4. Click Use Demo Credentials.
5. Try the Magic Link login option.
6. Observe that none of the authentication methods function correctly.

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Expected Behavior

• Users should be able to create a new account successfully.
• Existing users should be able to log in using email and password.
• Google OAuth should redirect to the Google authentication flow.
• GitHub OAuth should redirect to the GitHub authentication flow.
• Demo Credentials should log the user into the demo account.
• Magic Link should send a valid login email and allow authentication.

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Actual Behavior

• Email Sign Up fails with "fetch failed".
• Email Login fails with "fetch failed".
• Google OAuth is not functioning.
• GitHub OAuth is not functioning.
• Demo Credentials do not log in.
• Magic Link displays a success message but does not complete the authentication flow.
• Authentication is unavailable through all supported methods.

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Screenshots / Screen Recordings

• Sign Up page displaying "fetch failed"

• Login page displaying "fetch failed"

• Authentication options (Google, GitHub, Demo Credentials, Magic Link) not working

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Environment

• OS: Windows 11
• Browser: Google Chrome
• Node.js Version: Unknown (Production Deployment)
• FlipTrack Version / Commit: Production (Vercel Deployment)

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Console Errors

fetch failed

Additional browser console logs were not captured, but the frontend consistently reports a failed fetch request during authentication.

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Additional Context

Since all authentication methods fail, this appears to be a common backend or authentication configuration issue rather than separate frontend bugs.

Possible causes include:

• Backend API unavailable
• Incorrect production API URL
• Missing environment variables
• Supabase configuration issues
• OAuth redirect URI misconfiguration
• CORS configuration problems
• Backend deployment failure

This issue blocks all users from accessing the application and should be treated as Critical (High Priority).

[Khushi1310-nayak]

Hi @rushikesh-bobade, I'd love to work on this issue. Can you assign this issue to me?

[github-actions]

Hi @Khushi1310-nayak! 👋

Thank you for your interest in contributing to this repository! Please wait until a maintainer officially assigns you to this issue before opening a Pull Request.

While you wait, please consider starring ⭐ this repository to show your support! We review requests regularly and will assign it as soon as possible if it's available. Happy coding! 🚀

[TejasNere99]

Hi @rushikesh-bobade,

I would like to resolve this issue as part of ECSOC26.
Could you please assign this issue to me?

Thank you!

[Abhay2110s]

hi @rushikesh-bobade i want to really work on this issue
can you please assign it to me !

[rushikesh-bobade]

Hi everyone! Thank you all so much for volunteering to tackle this critical issue.

@Khushi1310-nayak, since you wrote up this excellent bug report and were the first to request it, I am officially assigning this to you! Since this is a production deployment issue, I recommend checking the environment variables on Vercel (e.g., VITE_API_URL or Supabase keys) and ensuring CORS is properly configured on the backend. Let me know if you need any logs from the deployment dashboard to help debug.

@TejasNere99 and @Abhay2110s, thank you for stepping up! Since we can only assign one person per issue to avoid overlapping work, this one goes to Khushi. However, we have plenty of other open issues, so please feel free to grab an unassigned one!