SARS Finding ways to not pay refund by messing me around in the extreme! SARS has got worse not better!

So I am owed a refund by SARS and they have started a seriously intense and prejudicial campaign to try and find ways not to pay. They send a letter saying that I need to update my banking details that HAVE NEVER CHANGED SINCE I STARTED PAYING TAX. The amount of information that I needed to send them was just short of a DNA test and now they have decided that my ID number (where the last digits changed with almost half the country over a decade ago) needs to be verified in person at one of their branches. They are simply finding ways to not pay