FNB making the rules up as they go with no Forex exchange policy

I recently returned from international travel with dollar notes that I wanted to exchange for rands. I went to my local FNB branch in Ceres. I was helped by the friendly clerk who asked for my Passport which I provided. We were almost finished with the process when the branch manager, Sonet Muller came and insisted on a source of funds. I informed her that it was spending money with which I returned from travel but she insisted on seeing a source of funds.

I asked her to send me a copy of FNB's Forex exchange policy so that I could see what the official requirements are. After multiple emails back and forth, Sonet was still unable to send me FNB's forex exchange policy. It seems like Sonet/FNB just makes the rules up as they go.

Time to find another bank.