Discount **** at pick n pay stores

I bought 2 potplants, the sticker on each item states...SAVE BUY 2 SAVE 20% My logical interpretation is, should I buy 2 of these plants, my saving in total would be 20% If 1 costs R200, and I buy 2, total of R400, then my discount would be R80. But no, at first NO Discount was given. When I checked my slip in the car, I noticed this. Back to the store, not helped in a friendly manner at all, I was given R40. On query abou the 20% discount, I was told no, it means you get 10% off 1 plant, plus 10% off 2nd plant. Equalling the "20%" off. A total ****, total manipulation and misleading advertising. If I could give 0 stars, it would be more appropriate😡