mislead by the tv adverti*****t

I went to pick n pay on Saturday because i saw there was a special for a box x6 of milk for R60 if you use your pnp smart shoppers card, which i did to find out that was a lie i had to buy 2 box meaning 12 box of milk for R120 but on tv its say 6litres for R60 and the staff was so rude and manager so arrogant and was forced to buy 12 boxes instead of the 6 that i initially wanted.