Fix Crashes on iOS & Android

My React Native app currently crashes whenever a user tries to log in on both iOS and Android builds. Startup is fine and normal navigation works, but the moment the login request is made the app shuts down. I have crash reports from Crashlytics, Xcode, and Android Studio that point to a possible null pointer in the authentication flow, and I will share those as soon as we start.

What I need is someone who can:
• reproduce the crash on a simulator or device,
• trace the root cause in the existing codebase,
• patch the bug without introducing regressions,
• confirm stability by running the full test suite and a few manual log-in attempts on each platform, and
• prepare a short summary of the fix so I can reference it in future updates.

The project will be considered complete once both builds survive multiple consecutive log-ins without crashing and I receive the concise report of changes. If you are comfortable diving into a cross-platform authentication module, let’s get this solved quickly.