Failure to update my personal and contact details

In August last year it appeared to me that standard bank had failed to update my account from elite to prestige, they had also failed to update my personal information despite several requests.<br> <br> I complained to standard bank ***, a lady named Zeenath put me through to Phumzile Vilakazi to assist in rescoring and updating my account details as well as my personal information.<br> <br> I went into the woodmead branch to meet with Phumzile, and submit to her a proof of residence and salary advice.<br> <br> Almost a year later my contact details have not been updated and a result the bank claims that they have not been able to get hold of me and they have handed over my account to collectors.<br> <br> I have not received notice from the bank advising me of any default or even the fact that they are handing over to a third party.<br> <br> Is it legal for the bank to 1. fail to update my contact details? 2.Contact me on the outdated details which they failed to update? 3. handover my account to a third party without any real written notice to myself/<br>