Price discepancy

Terrible, terrible service from Ok furniture, Malelane. I wanted to buy a fridge which was out of stock on Christmas eve. I asked if I could buy the demo model in store and the manager advised that there is a discount on demo models on 26 and 27 December so I should come back on 26 to qualify for the discount which I did. The supervisor on duty advised that 24 December the prices went up, yet the fridge price was still marked at the same price. As a consumer I should pay the price advertised as well as the discount promised but the staff refused as they admitted they made a mistake by not changing the price and they would get into trouble. I was not advised that the prices were being increased, if so i would have bought the fridge the same day. After calls to the manager and endless attempts to get the fridge at the price advertised I took a photo of the fridge and the price it was advertised for and left behind very unhelpful and very dishonest staff. I feel that I should have been able to purchase the fridge at the price advertised but feel as a customer, I am taking the brunt due to staff failing to do their job.