Collection Method

Good Day

I have an overdraft with Nedbank yes it is behind with payments however in the past three weeks i have been receiving calls from different cellphone numbers to mention a few ********** , ********** and ********** these numbers/calls are from different consultants working for the Nedbank's collections department...How does Nedbank expect us to divulge our personal information to a consultant calling from Nedbank with a cell phone number..***** is at its worse out there dont make us feel like not worth being valued now just because our accounts are in arrears the worst part of all i did not receive any sort of communication from the bank to advice that we must be alert that they will be using cell phone numbers to address formal /business issues..This is totally uncalled for.