Asked after purchase for a delivery fee

After showing Free delivery for a R2000+ purchase I then get an email that asks me for R250 for delivery and when I query this, the agent just says that's what the system requires. So terrible UX in their check-out delivery steps because it's obviously totally misleading to the user and also - who still charges delivery for such a large amount? All others qualify you for free delivery above a certain amount. My recommendation - use one of their competitors, you'll have a far better experience.