Dear User,
Good day!!
Apologies for the inconvenience caused and please don’t worry, let’s work together on your concern and move towards a resolution path.
I understand your concern and would like to let you know that the folder you are trying to remove is a folder in the SharePoint Online which is added as a shortcut to your OneDrive and when the folder in the document library added as a shortcut, it’s not possible to sync the document library.
To remove the shortcut folder, please follow the below steps and check the outcome:
Open the File Explorer> Go to the OneDrive synced folder> Right-click on the shortcut folder name> If you get Show more options, click on it> Remove Shortcut.

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If you are not able to find the Remove Shortcut option, please follow the below steps:
Open the OneDrive for Business in the browser> My Files> Select the shortcut folder> Remove shortcut> Wait for some time for OneDrive sync client to sync the changes and remove the shortcut folder.
If still the shortcut folder appears even after removing it, please reset your OneDrive sync client: Reset OneDrive - Microsoft Support
Appreciate your patience and understanding. Have a great day!!
Best Regards,
Sophia