Voucher problem

I received a Voucher for my birthday valid for 12 months. The sms is as follows: Happy birthday! Enjoy R100 off your next Beauty or Hair Salon Treatment @ Dis-Chem Salons with voucher code *** . T&Cs apply, valid for 12 months. After taking a while to choose a hair product and standing in the que for about 20 minutes I was told that I am only allowed to choose Bionike products. I really dont find this amusing. I am very disgust!!!!