Terrible customer service

I was at Sasol Arkwright(16 Andries St, Wynberg, Sandton, 2090), enquired to a Cashier named Slyvia. Asked her about the 1.25L breturnable bottle policy. She was very condescending. A simple question. Do I get my money back through card or physical coins because it's just R3 i mean cmon... She said "bring back the slip and we will give you your money back." My question was HOW? and she kept repeating " bring back the slip and we will give you your money back did I make myself clear". All she had to do was answer the question. Who does she think she's talking like that too? Poor customer. She better learn to be a people's person cause it's her job requirement to interact. Sies!