All of your clients that receive files from thier customers are probably doing it wrong. They already own a better solution
What was happening is that files and folders were appearing in OneDrive for a moment, then disappearing, then reappearing, then disappearing. The client reported this as OneDrive “flashing”.
Microsoft long promised a functional and secure file-syncing solution that works. It took a while to get here but they’ve delivered that us and more.
We now have a really nice feature-rich solution for receiving files, keeping data safe, and automating the cleanup task. It’s been a long time coming.