A Microsoft file hosting and synchronization service.
1
If you have a Microsoft 365 subscription, log into OneDrive in a web browser (https://onedrive.live.com/), then click the gear icon at the top right and select Settings.
On the left, click 'Recover my OneDrive' and try using that process to recover the deleted folder.
2
If that process is not successful, the only hope you have is to try to use a 3rd party recovery utility to undelete and recover the folder on your computer or device the folder was originally created on.