Cannot rename my own ipynb file with Jupyter Notebook

It has been working fine when I worked on files under a dropbox folder (say, folder_x) in Windows 10, but when I go to another (new) computer with Windows 11, I cannot rename my own ipynb files in the subfolder folder_x1 under folder_x, the error message is:
An error occurred while renaming “test2.ipynb” to “test3.ipynb”.
Cannot rename file or directory ‘study.finlab/test.finlab.api/test2.ipynb’
I need to create another subfolder folder_x2 under folder_x in Windows 11 and then I can rename my files there.
However, when back to Windows 10, I can rename files in both folder_x1 and folder_x2 with no problem.
Please kindly shed some light on how to fix it, thanks in advance.