30% increase mid-purchase

Yesterday I was in the process of purchasing 3 sets of 4 personalised fridge magnets as an anniversary gift. While uploading the 8th(out of 12) picture, the page freeze, refreshes itself, and the price increases from R99.95 per set to R129 per set. Their customer care is willing to give me a voucher for the R90 difference, but I can't use it in conjunction with the R100 voucher I already have, still leaving me to pay R100 more than I would have originally. They also subsequently deleted this complaint off their FB website - inconvenient for customers to know they inflate the price (non-sale) products by 30% mid-sale without any indication. I order from Netflorist on average once a month, and in the last 12 months spent in excess of R4000 buying from them. I will never again utilise their business. I would have just left it with the FB complaint yesterday and to not buy from them again had they not deleted the feedback I gave on FB.