Hi Demontwe,
As mentioned above that, when you open the file and download it to your PC that time are you able to access the file?
If yes, then how and using which application you are able to open it?
If it is Acrobat Reader DC then you need to save the file to the "Document Cloud" storage, so that you can access it via Acrobat Reader mobile application.
- Open file in Adobe Reader DC desktop application>File>Save As>Save to "Document Cloud" storage.
- You would only be able to do that when you have the file's permission, which you can check Right click on doc>Document Properties>Security
To access the file on mobile you need to have Adobe Acrobat Reader mobile application (Sign In using same Adobe ID) Adobe Acrobat Reader - Android Apps on Google Play
Let us know if this doesn't help.
Regards,
Akanchha