False advertising from Boxer Build

Today I went to boxer build in Gamalakhe to buy cement based on the advertised price, which is R75.90 only to find out that it’s R78. The manager said that that’s the price and it’s final. This is not the way to do business and to make matters worse I have been buying all my cement from them. I won’t lie I was very dissolved at how boxer handles their customers, for a reputable company they really failed to attend to their mistake. I even have a photo of the adverti*****t.