Marketing ****s and poor service

I was very excited to get a voucher for 15% off on a car seat from Toys R us from Discovery. So off I went to Toys R Us on the 10 July and took a Joie Stages car seat. When I went to pay at the till- no discount with my Discovery Vitality card and then it wouldn't accept the WI code on my 15% discount voucher either. Eventually a manager arrived and tried again, it continued to give the same error. She told me that I need to contact Discovery Insure because she doesn't know why it won't accept the code. I immediately contacted Discovery Insure and spoke to Sibu, he seemed very confused, took down all the details of my query and asked me to hold, I told him that my phone might die and asked him to please call me back, he said that he would, I still haven't received that phone call! I called back an hour later and spoke to MK, he also seemed unsure and told me it was for any car seat, when I then asked him that he needs to give me an explanation as to why the code wouldn't work he placed me on hold. After about 15 minutes he eventually told me that its for selected brands of car seats but he can't access the list and he has sent an email to support. He promised to get back to me in 2-3 days. I still haven't received any communication, 2 weeks later? It was never openly or clearly advertised that you can only redeem this voucher on selected brands, the voucher simply says 15% of a child car seat, surely it should say selected seats? So after my phone call I went onto the Discovery site, after some searching I found the list. Why do you as Discovery offer this discount to your clients? I would hope that it would be to ensure the safest way for children to travel. Why are most of these seats on the list substandard with no safety reviews or standards and only sold in SA. The only brand on your list that is ok, not great, is the Chelino. Why have I not received any further communication as promised? Why is it not clearly specified that its for selective seats only? Why is no one in your call centre equipped to deal with this query? Why don't you have a comprehensive list with seats with good safety ratings? This is just a marketing strategy to get people to insure there vehicles with you but there is not actually any benefit!