Many of the pdf files I add to Notebook work fine but in some cases when I try to open them on the Android App I get a message saying "Unsupported Type. Psst! You are using an older version of the app which does not support this note format. Please update the app to view the content."

When I push the update button, it goes to the Google Play Store but has the same version of the app which I already have. This has gone on for a while, so there have also been updates since this started. 

The pdf files work fine on the desktop and web versions.