False Advertising and Terrible Service Delivery!!!

I am very upset at Edgars and their online service!!! I purchased some items online on 31/07/2017 which was 2 Clinique make-up products, and at the time they had a promotion going on which stated that if you buy 2 Clinique products you would get an 8 piece Clinique gift set free! When i visited the Boardmans store in La Lucia on 14/08/2017 to fetch my items my gift set was not there!!! I called customer service straight away and they escalated the matter! Only to be called back that afternoon to be told that they will be giving me a R100 voucher!! This i find to be disgusting and a cheap way of worming their way out of this situation. Firstly the only reason why i bought the make-up was because of the Free gift set which is valued well over 600 rand!!! I told them that i do not want the R100 rand voucher as i am not happy with that and you cannot even get anything in Edgars for R100 rand! Up until today i have had no feedback from them! and what is even more disappointing is that i have seen some of the gift sets at the stores! they cannot possibly tell me that there is no Stock available and i ordered this items during early days of the promotion!!! This is false advertising and very disappointing as i wanted that gift-set this is why i bought the items in the first place! I do not want a cheap R100 voucher!!!