Edgars Sandton City offered me bad service

I bought sale items with 50% off marked price and they refuse to give me 50% discount that they are talking about. When the customer care lady asked the lady who was working in the floor where they sell beddings, she was very rude to me and tell me that what i see on the sticker is the price i must pay. The security woman came trying to make me understand that there is no 50% discount on the sale tag. They treated me like i am stupid i do not understand.I understand how the sale works and i have bought so many sale items since i had the account. My account has been active for several years. The worst thing is the assistant manager Steven instead assisting me he blamed me why i left the store without talking to the store manager.