Anyone know the best iphone data recovery software still works now?

The "Hidden" System Cache for specific file types on an iPhone refers to temporary files stored by the system or apps that are not directly accessible through normal user interfaces. These caches can sometimes contain data related to photos, videos, messages, or other app files, but they are typically not recoverable through standard recovery methods or free iPhone data recovery software because iOS is designed to protect system integrity and user privacy.

This is a long shot but worth a quick check for certain file types.

Safari Browser: If the file was a PDF or document you downloaded via Safari, it might be cached. Go to Settings > Safari > Advanced > Website Data. This won't list files neatly, but it shows cached data. You can't easily browse it, but its existence proves the app has stored data.

Spotlight Search: Swipe down on your home screen and search for the exact name of the file. Sometimes Spotlight's index still knows about a file that is no longer accessible.