Please Help Errors While Adding

Hello, I am trying very hard to transfer my ebooks to my new Kobo, but every time I put any of them into Calibre I get an error message saying the following

"calibre, version 9.8.0
WARNING: Errors while adding: There were problems adding some files, click "Show details" for more information


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Failed to add the file /Users/dennismader/Downloads/E books:pdfs/A New Day.epub to the book: /Users/dennismader/Downloads/E books:pdfs/A New Day
With error:
Traceback (most recent call last):
File "calibre/gui2/add.py", line 492, in add_formats
File "calibre/db/cache.py", line 2182, in add_format
IsADirectoryError: [Errno 21] Is a directory: '/Users/dennismader/Downloads/E books:pdfs/A New Day.epub'

I would appreciate any help to solve this issue!