Highly irrate and upset PLEASE HELP

I am so irrate and upset. After being handed over by Fnb for my outstanding overdraft to debt collectors I made repayment arrangements with them and have been maintaining the arrangement. Now I see an sms to say that they have not received a payment from me since September. According to a new debt collector who has taken over, they want me to send then my banking details. I have tried to call Fnb to confirm a change in debt collectors before giving my banking details out, but I just get sent from one incorrect department to the next or lost in the stupid bot service, even after been given direct numbers for the Overdraft legal department. I'm trying to pay off my debt and cannot get through the correct department. PLEASE HELP!!!