Cost for your own money

As a long time customer of FNB (some 50 plus years - since the days they were Barclays Bank) I was appalled at a demanded charge for attempting to exchange a R100 note for R20's (you cannot request an ATM to dispense what denomination you wish). I was informed by an indifferent Teller that it would cost R10.00 - i.e. 10%. When I complained to the Manager he said it was a Head Office instruction - for exchanging my own money ! I walked across the mezzanine to ABSA where a cheerful Teller obliged and confirmed "no charge", and when thanking her I received a reply "Pleasure sir, look forward to seeing you again". I returned to the FNB Manager and told him of the assistance from ABSA for which he gave me a blank expression. This is iniquitous and frankly ****************, FNB.