[Locked] IOS Missing Email Attachment on PDF

Hi I could previously receive an encrypted email on IOS, point it to Adobe, enter password, see email and then open attachment.

Now however, when I click on attachments it says 'no files in this location'.

I have just reinstalled Adobe Reader from the app store so it should be up to date.  I have IOS 12.0.1

Any help would be really appreciated.

Thank you.