Staff changing my telephone number - unable to get OTP's etc

I've been experiencing this problem for the last 9 years. Had this account for about 20+ years. But, 9 yrs ago, my son went to varsity, and he too opened an account. Since then, someone changed all the tel.nrs on my account to my son's tel nr. No idea how that is even possible, we don't share initials/ numbers / addresses etc. Since then, I don't get payment notifications / OTP's to my number. I've complained and fought about this 6 times before - each time, I'm promised that the problem is resolved, but within a year/2 it happens again. My father passed yesterday and I've been trying to book flights, car hire, accommodation, but with no luck, because all OTP's are sent to my son's phone which is not with him (he is in class all day - teacher). This happens on both credit + debit cards. I've made 8 calls his morning - gets transferred all over and then cut-off. Have sent 2 e-mails to my so-called private banker, Irene Molepo, but no response. Her number now also doesn't exist any longer! This is ridiculous!! I can't phone anyone / can't get hold of Irene / nobody can help. How am I suppose to get to use my OWN money in my OWN account, especially now in a time of emergency. Do you still have any people working there??? You can easily take my money each month for bank fees, but there is NO SERVICES rendered from your side. Some idiot keeps chancing the details on my accounts, without my consent. Last year, someone changed my address to something else, just to get their hands on my new debit & credit cards. It seems you can no longer be trusted and that ********* behavior + non-existent service is at the order of the day!!!