2 T-Shirts 30% off, 4 T-Shirts NOTHING OFF

So they have a 30% off 2 T-Shirts sale. I buy 4 and the discount doesn't reflect so I have a live chat with Samantha Cathryn B. Turns out you can only buy 2 at a discounted price, so I would have to make 2 purchases for 2 T-Shirts each and pay R60 postage for each order. The ad should say Buy 2 T-Shirts get 30% off, Buy 4 T-Shirts Get Nothing Off. Sorry, won't be supporting you guys anymore