First of all, thanks for using Paper - I am a big fan too
Now as per your inquiry, are you by any chance trying to add this Paper doc to a folder of your Dropbox account?
Bear in mind that Paper docs and Paper folders are separate from your other Dropbox files and folders, and cannot be added to regular folders in your Dropbox. One thing you could do is downloadthe Paper doc in your device as a Word document (docx) and then upload the file as you normally would with any other file in your Dropbox account.
I hope this helps in a way. Please let me know if I understood correctly and we'll take it from there if needed.
Thank you in advance and have a wonderful weekend ahead!
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