Bidvest Bank 2024 mandate system seriously flawed

I have received the 2024 Mandate from Bidvest Bank, supposedly being handled by AZA Finance. My bank account branch code has been changed from the previous year. I have held the same bank account with the same branch code for the past 40+ years. My transfer is being blocked because the branch code is incorrect. AZA finance simply sends out a generic "we are attending to your query" email, and the phone number supp**** does not work, just an automated message then the call is terminated. The automated response says I must change details on the side that is paying into my account. Payoneer does not use branch codes when transferring payments, therefore, I cannot change something that does not exist on their side. The fault lies on the part of Bidvest Bank, where the incorrect code was loaded. I have urgent need of payment and have no idea how to rectify this as Bidvest Bank appears to be unconcerned. Perhaps Bidvest Bank should manage these mandates themselves, or at least appoint a company that knows what it is doing.