OK Furniture Marble Hall misled me, R2800+R400 into drain

I am in Pretoria and I wanted to buy freezer for home targeting Black Friday special. I decided to support Ok Furniture at home (Marble Hall) as I do all the time with the help of their sales person/Dorcus. I called sales person on the 28/11/2019 to inform her of my decision and asked for assistance, as I will send my mom money and she will come buy this chest freezer there and alluded that she does not have a cellphone, she responded “its fine I will come back to you”. On the 29/11/2019, I called her again to confirm that she is coming to buy and she does not have, cellphone please let me know when she’s there. The same sales person responded its ok let her come I will call you. When the old woman (my mom) gets there, sales person told her your daughter told me about you. My mom told her; yes, I am here to buy freezer that is on today’s special. They were 3 freezers on black Friday special, I needed Hisense R2990 but because she said she will come back to me when my mom arrives at their shop, I waited. That sales person showed her the Defy of R2800 and made transaction. My mom got a delivery from someone outside (R400) then freezer was delivered. For me not receiving a call from sales person I assumed my mom did not go to OK Furniture. Around 6pm my mom arrived home and my dad called us to talk to her we found that she went to OK Furniture but they sold her the wrong one. I immediately called the sales person and asked why didn’t she call me as agreed, she said it was very busy at the shop BUT interestingly she knew that it was my mom and she took her money and chose her the DEFY freezer on special. Anyway, sales person said to me if the delivery person is still around town tell him to bring it back, I told her I don’t have his cell number. She then said, please call again tomorrow we will fix this. Today when I call, the sales person and the manager/ Johannes are telling me there is nothing they can do the special was for yesterday. The manager is even emphasizing that he is only hearing this today and says I spoke to sales person so it’s our thing (myself and sales person) as if the sales person does not represent OK furniture. I started explaining this error yesterday before they close (29/11/2019) I was asked to call again the following day so they fix this mess. The respond was an escape so that they will boldly tell me that “there is nothing we can do, the special was for yesterday only”. R3200 I saved for long time went worthless. THIS IS TOTALLY NOT FAIR.