Treating customers unfairly

I drew money from a standard bank ATM at a Spar in Malvern Johannesburg, one of the R100 notes I drew had ballpen ink on it i tried returning it at to one of your standard bank branches in benmore sandton johannesburg they said I needed to return it to the Malvern branch I go to the Malvern branch they say they not allowed to change it I am supposed to take it to the Reserve Bank now I find this very irritating that you guys accepted the money thats why it was in your ATM now it must be my problem waste money going up and down for one R100, is this how you treat your customers then I really dont want to be associated with you and I will make a follow up with the Ombudsman to see if this is the way standard bank operates.