OTP's going to 3rd party. Security risk.

My father who is retired and is 84 yrs of age lives with me. Both he and I are life long loyal Standard Bank customers. Recently we needed to change his email address. This process started approximately 6 weeks ago and has been a complete failure by Standard Bank. Between myself, my wife and my son we have taken my dad to Standard Bank Northgate at least 6 times if not more. On every occassion the client services person has assured us his email address and OTP will be updated. Today six weeks later my fathers OTP's still go to a 3rd parties email address which is highly irregular. In his personal details his email address is correct but his OTP's email address is not. Under no circumstances should my fathers OTP's be going to a 3rd party email address. 6 weeks later my father still cannot transfer his pension because of the OTP destination. What do we need to do to get this RIGHT !!! Phoning client services is also a complete waste of time. No one ever answers.