False advertising

I went to MT Price Middelburg on Saturday and saw n red medical tin marked R30 off, and on the bin a price of R299.00 so i opeende it and neatly inside a smaller tin asuming it comes togheter i went to the till as he rang up the tin he the only informs me that each one is price seperatley but it cones i a set, nowhere near the shelve is any notice that it comes seperatley!!! What now??? I left it to get feedback, its not acceptable to pack if as a unit and then sell it seperately???