I am unable to sign in to MyBT as the process is to send an authentication code to my mobile phone. My mobile phone has been compromised and I now have a new mobile number. The authentication code is being sent to my now defunct mobile phone. I can't get past this to amend my details with my new mobile phone number.
try phoning CS 150 or 0800800150 from your mobile and they should be able to help you get account updated