We have noticed that some people have had problems using the BNF App, where despite having a workable NHS Athens username / password the app appears to indicate that you are not allowed access.
We have found a strange work-round that seems to work.
Once you have set up your NHS Athens username go to the NHS HDAS databases and log in. If you are able to login OK, select a database (any will do), then log out. Then repeat the process of logging in and out again.
Now go back to your BNF App; it should work OK and let you log in.