Same problem with me. Tried uninstalling bt mail and reinstalling but no better.
Come on BT let's get this sorted
I have moved your post to start your own thread as your problem is not the same as the thread you posted on which is about problems with the Gmail app.
Are you either a BT broadband customer or paying for Premium Mail?
Also having this issue. Headers download to bluemail or edison, but content doesn't. No issues with webmail or Outlook client on Win10 PC. Started 3 days ago, never an issue before that.
Have reset cache, deleted and reinstalled app, installed Edison to rule out Bluemail, restarted phone etc. This is a BT email issue with Android only- no problems with Gmail or downloading to iPad/iPhones etc.
I am a BT broadband customer.