extremely poor service by assistant

I went to truworths on 16/6/2015 to the cellphone counter and was assisted by Samkelo, after I paid, I went back to Samkelo and he started doing what he needed to do, I then asked him if interest is charged on 6 months and he said yes, I told him but the person who helped me only mentioned the purchase can only be 6 months nothing about interest. We continued with what he needed to do and then he told me to sign that it is the phone I'm purchasing and my details are correct which I checked and signed, then he gave me another page and told me to sign, I asked him what am I signing for and he said the warranty, I told him I can't just sign and he needs too explain this warranty to me, he then told me I must read it he does not have to explain it to me, I told him he needs to explain it to me as it is his duty to be transparent and make sure that I am aware of what the warranty entails. He refused and told me no need to fig and stood staring at me, I asked for the manager and he did not call her so I went and called her. I explained to her and she said she will have a word with him. He kept glaring at me and I showed her, he did not explain and I did not sign. Most appalling service.