Aggressive teller.

I went into EB Hyde park to redeem some gift vouchers that I received, getting to the till with a R140 book I handed over a R200 gift voucher and asked how change was given, I had another R100 voucher and if they didn't do change I planned on using the R100 voucher and cash. The very nice teller in the pink hoodie told me that she would give me the change on a gift card, I was quite happy with that and asked her to add the R100 gift voucher on the gift card too. Whilst doing this a young man with red hair tied in a pony tail walked up to the lady helping me and rather rudely informed me that there was no change given on gift vouchers, I was a bit floored but decided to take the calm approach, he promptly left to go find out what to do. I was asked to please step away from the teller as there were people waiting to be served. Standing around waiting for them to either give my vouchers back or as me to leave, he returned and said that a gift card will have to be issued. I told him that my shopping experience was turning to a unpleasant one, he quite aggressively asked me why. I walked out of the shop to calm down. I phoned the store to speak to a manager but none was available. . . .