Sync data server to local and local to server using C#

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C#

OneDrive

Hello,

I am using OneDrive Rest API and create a web application. It works fine. I have also created one Windows Service and use FileSystemWatcher class of c# library. It sync changes to OneDrive account whenever the local OneDrive Folder is Changed. But when user perform changes on OneDrive directly I am not able to sync that changes with my local OneDrive folder. Hows that possible if any changes are done on OneDrive then data will be automatically update with my local OneDrive folder?

Thank you

What I have tried:

FileSystemWatcher watcher = new FileSystemWatcher();
               watcher.IncludeSubdirectories = true;
               string _path = "C:\\Users\\srust\\CloudStorage\\OneDrive";

               watcher.Path = _path;
               watcher.EnableRaisingEvents = true;
               watcher.Created += new FileSystemEventHandler(watcher_Created);
               watcher.Deleted += new FileSystemEventHandler(watcher_Deleted);
               watcher.Changed += new FileSystemEventHandler(watcher_Changed);
               watcher.Renamed += new RenamedEventHandler(watcher_Renamed);

And Then Implement all methods as per API Request.