No Response to complaint PLUS shocking Price increase.

SHEBA CAT TINS. I sent an email to Makro Customer service a number of weeks back complaining that I was over charged on a promotional item. No response. I took the 24 unit box back today for a refund. Got my refund but first had to get the manager as I had not returned the items in 14 days, yes it says that IN the returns section, but not on the till slip. Subsequently went to the shelf to get a replacement flavour to see that in 3 weeks the price went from R13.39 (promo price was R12.00 per unit) to R15.45 - increase of R2.09c PER UNIT IN LESS THAN A MONTH. That's a 15% INCREASE in price. How do you explain that Makro?????