A Microsoft file hosting and synchronization service.
Another option is Restore your OneDrive, which can roll your OneDrive back to an earlier point within the last 30 days if you have a Microsoft 365 subscription. After that, also make sure the OneDrive desktop app on the PC is signed in to the correct account and that Documents is still included in OneDrive folder backup, because that can affect where Office looks for the file.
https://support.microsoft.com/office/restore-your-onedrive-fa231298-759d-41cf-bcd0-25ac53eb8a15