Rude

I was in the shop to return a item that I bought, the snr manager was so rude with the fact of helping me, when i asked for my cash back she said that they don't do that so how come I should pay cash if PQ don't return cash back? when i asked for a voucher she refused and said that I should pick something now in store or leave the building, I really felt ******ly abused at the moment while the till ladies and the security kept laughing at me. So management if this is how you treat white people I will never buy from you again!