Unable to copy pages from Authentisigned PDF to new PDF Document object

I have a pdf document that has been signed via Authetisign.  
I need to make some modifications to the document, knowing that this will break the security seal.
To expedite the processing I am splitting each page of the document into individual pages.
As I attempt to copy a page from the signed document into a new document I receive an error I can not find any documentation on.
Please advise how to solve or circumvent this error.
Thanks!

            

Hi Josh,


Thanks for using our API’s.

Can you please share the resource Signed PDF file, so that we can test the scenario in our environment. We are sorry for your inconvenience.