Worst Service Provided

After I send my dad to purchase the Nike Airmax Thea a size 4.5 for me on the 02 March 2015 at Sportscene Somerset Mall, I was highly disappointed when I saw one shoe was a size 4 and the other shoe a size 4.5 after the lady in front assured him she checked the sizes. HOWEVER I went in today on the 03 March 2015 to exchange it and receive the right sizes but was told that they already sold it like that to another client(im sure that client is unaware of this because they themselves were unaware) I was not offered any other options like checking if another Sportscene has my size I was simply told they dont have and they don't know when they will get more stock in. Customer Care is very important and I have been a loyal customer for years but with this kind of service I will take my business elsewhere as they clearly dont need it.