Bad service

I did a shopping in Potchefstroom and I bought long Johns at woolworths, only to find out when I arrive at home in Mafikeng that they are white in color so I returned them to woolworths the Crossing in Mafikeng and they told me that they cannot take them as they regard them as underwear but I tried to reason with them that they are not used they can check them because it will show so the manager told me that I did a mistake and they cannot be accountable for it. I am not happy at all with that answer. I thought that they will check it and confirm. That’s really rude to say that to a customer, I do not have money to buy the other one. So I thought they will see to it how best can they assist me, instead they give me an attitude.