It is working properly from our site, https://wpdmpro.w3eden.com/download/xlsx-file-test, I think it may have a conflict between your plugins or theme. Can you test disabling one by one other plugins for testing if there any conflicts. you may also switch theme to another for checking.
The CSV file you are sharing has the categories what you are claiming issue, so the the issue is happening, now your shared URL is not valid to download the CSV file. Please kindly check.
Hope you are well. Please kindly share the order id details , thus I can forward it to our related team authority for further checking. Please kindly check.
Hope you are well. And sorry for the inconvenience. If possible, can you please, give your temporary wp-admin login details in a private reply to check the issue.
If possible, can you please, give your temporary wp-admin login details in a private reply for checking the issue. Thus I can have a close look what is happening. Please kindly check and let me know.
