Makro price deception

I ordered some items online which were advertised under Makro's 'R100 deals' campaign. Five items were ordered at R100,00 each as per the advertised special. Their system invoiced me R150,00 per item, which I paid in order to complete the transaction and to secure the purchase. Upon receipt of the goods, I immediately lodged my complaint, having hoped (in vain, as it transpired) that the mistake would be picked up and corrected along the way. After almost three months of obfuscation, all I got from them was a string of feeble apologies, silly excuses and an sms voucher for R50 of the R250 that I was overcharged