poor service

I called the AB head office. I spoke to Lebo at customer care a week ago requesting for my prescribed letter, but she refused,, saying she couldn't access my account unless I went to the branch to change my cell phone number. What is the purpose of the POPIA if not to confirm my identity? I need My prescribed letter to be email d to me. Why do I have to go to the branch when something can be emailed to me?