Unable to help

I have been trying for the past few days to get assistance to log in to my banking app. I am currently in the UK and got logged out whilst here. In order to get back in the app needs to send an OTP to my cell number. This should be an easy case of calling the branch to update my contact details once I have gone through a rigorous security check. But NOOOO. The branch does not have the authority to do this over the phone. Call the contact centre. Did that. The contact centre says the branch should do that for me and DO have authorisation to do this. Call the branch again and get the same response. Again they say call the contact centre. Seriously???? I am calling from the UK can cannot just pop into my nearest branch. There must be some system in place for cases like this. The most unhelpful bank ever in this case.