Complain

I found 2kg Russians on shelf for 85.00 and when i went to the till to pay it was 112.00 so i told the lady who was assisting me about the price that i saw she told me to go and bring the price i saw and i did that... but she failed me and her manager who was not interested in what i was saying....very disappointed about the service especially from the manager who gave me a funny look ,and this is not the first time I am experiencing this poor service from till operator and their manager