Hi @Karl Chan,Thank you for posting in this community.
1.Please try deleting the file without using PowerShell.
Please try deleting the files in OneDrive Online (this step simply moves the files to the Recycle Bin, the overall storage space does not change), and then emptying the two Recycle Bins.
2.According to your description, you expanded your OneDrive's storage space, please check the bottom left corner of the OneDrive Online page to see if your OneDrive's storage space has been expanded correctly. If your storage is not expanded, please refer to this article to configure it. Please try deleting unimportant files again.
3.After you delete a file, I recommend that you modify the file version control settings for you. Reduce the number of versions so that it doesn't cause your OneDrive memory to fill up quickly.
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