OFFICIAL FICA PROOF OF ADDRESS SUDDENLY NOT ACCEPTABLE AFTER YEARS???

I have been a Bidvest customer for many years. I am obliged by law to provide current FICA documentation to all financial institutions. Since 2013, I have rented accommodation on farms and therefore have no utility bills in my own name, nor do I have any accounts which show my physical address. I have moved 4 times since 2013 and each time have provided Bidvest Pietermaritzburg branch, which has now closed, with an official declaration from my Municipal ward councillor as proof of address. Now suddenly this is not acceptable, although the other 4 financial institutions I use readily accept it (Absa, African Bank, Coronation and Stanlib). Strangely, Bidvest will accept a copy of my lease, the contents of which, apart from the cover page, I regard as confidential. Now they say they will accept a "statement not older than 3 months", which does not show my physical address. I have asked them to provide the reason why this official document is suddenly no longer acceptable, and from when, failing which I shall simply give notice to close this account and invest elsewhere. They have declined to answer this question. This is a serious matter which I will take up with the Municipality pending the reason for the proof being declined.