Hello!
The error indicates that your React/Realm Sync app is trying to access a Realm app in a region where it’s not available. Ensure the app is deployed in the region you’re requesting (US-VA) or update your client configuration to match the server’s region (aws-ap-south-1). For example, configure your Realm client with the correct region in your React app. If necessary, consider deploying the Realm app in multiple regions or consult MongoDB’s documentation and support for further guidance. This should resolve the 404 error related to regional availability.