As I and others have explained. If you can log and use your email address it is not and email problem.
You were trying to check your status on BTWifi, hence it was moved to the board that deals with BTWifi problems.
It just so happens that with BTWifi, which is what you were checking in that link you posted, requires you to use your email address as a user name.
It could just as easily have asked you to select anything you want as your user name but BT in their "wisdom" chose to have users use their BT email address. Some "newer" users happen to use their BTID which is not necessarily their BT email address.
What has probably happened in this instance is that your user name, which happens to be your email address, is not being recognised and needs re-set by BT.
I fully understand what a user ID is. Your statement that "What has probably happened in this instance is that your user name, which happens to be your email address, is not being recognised and needs re-set by BT." seems to be plausible. However, before I enter the labyrinth of the BT Call Centre, can you please explain in simple terms why you are convinced this is a wi-fi problem - as this information may help me in my discussions with BT. Thanks
As it would appear that my post has been edited by a moderator for some unknown reason I will no longer be posting on this thread.