STUPID BANK

My daughter went to FNB to open an account for my grandson who has just turned 20 and has entered the work place. Now as they reside with me they needed proof of my address via a rates account or an electricity account plus a signed affidavit with a copy of my ID certified by a commissioner of oaths. This I did. Went to the local police station produced my ID signed the affidavit in front of the officer. He then stamped it and fill his particulars in and signed his name. So off to FNB they go with proof of address and he signed affidavit only to be told that FNB dont recognise the signed affidavit so she is given another form from FNB that I have to sign before they will open an account for my grandson. My complaint is since when does a bank not accept a sworn affidavit signed in front of a police officer. They give my daughter a form that she could have walked out the bank forged my signature and the bank would be none the wiser. Now how stupid is the bank in refusing to take a sworn affidavit signed and stamped in front of a police officer which is accepted in all other institutions but not FNB