Fix React-Native Supabase DeepLinks

I already have a React-Native app wired to Supabase, but the magic-link flow is broken and deep links are not reaching the app on either iOS or Android. My main goal is rock-solid user authentication; once the link opens, the session should be stored and the user redirected correctly.

What I need from you
• Pin-point and fix the magic-link / deep-link handling for both iOS and Android (expo-linking or react-navigation preferred).
• Resolve a small but recurring data-inconsistency issue that shows up right after sign-in—records sometimes fail to sync to Supabase.
• Hand back a concise patch or sample repo plus a step-by-step note so I can replicate the fix in my main codebase.

The app is built with React-Native (Expo), Supabase JS client, and react-navigation. If you know this stack well, the job should be quick; I’m only after a working fix, not a full refactor.