Dishonest management and staff

On Monday the 6th of June I went to Boxer Mitchell's Plain to buy bread and then I saw the shield was on Promotion and took 3. When I got to the till it scanned R23.99. I then told the cashier that it shows R15.99 on the shelve and went to get the ticket to show her. She called for authorization and the supervisor didn't even acknowledge us and the cashier told us she's coming now. We waited and the supervisor came back saying she can only override 1 to which I rep**** it's all on Promotion. She then left again. While waiting another gentleman came and said the manager was coming soon. We waited almost 20 minutes and I decided to go towards the office and see what's the hold up. I was told that the Manager was on a call he will attend to us soon. I went back to the till and saw the manager come out of the office and walk around to the back of the store towards the isle with the underarm. My husband then went to ask him what's the hold up and came back to me saying he's removed the ticket. I went back to the isle and the manager and the gentleman that came to me saying that I will be attend to soon was there and they were acting all surprised when I asked what happened to the other Promotion ticket and whilst talking to them another customer also asked the price and not one of them answered her. I then showed the manager a shelf edge ticket indicating the R15.99 price then the gentleman leaned forward wanting to remove the ticket just as I took the photo. I have never been disgusting as much as I was yesterday. They made me look like a lier and it goes against my morals to be dishonest.