Misleading product and poor telephone etiquette

I purchased a special deal voucher on Groupon(groupon is awesome) for a wash, cut, treatment and hair colour at Charlotte at Studio One for R169 which I thought was amazing. The fine print on the voucher does state that for hair longer than a bob, will be charged extra. However, when I phoned for an appointment, I was told that the additional cost is between R300-R350 because my hair is double in length. That is a complete *******! I need to pay more than three times the purchased voucher price for slightly longer hair! I complained about this to Charlotte, who told me that I needed to whatsapp them in order to see the pricing chart for the different lengths, which in no way it was advertised as such so how would a customer know to do this? This special is totally misleading. Charlotte was very stroppy during the conversation with me and later addressed me as \listen here sweety