Not a happy customer

On the 1st Feb I purchased a size 4 sneaker from maponya mall. I didn't fit it at the store because I was in a hurry. I got home to try the shoe on and it didn't fit. So I called 6 cross trainer branches to find out if they had the shoe in a smaller size so I could exchange it, all the people I spoke to said \No\". Saturday(6th Feb) I went into trade route mall branch to get an exchange or a refund. I was told there was no size and I was also then informed of the no refund policy that I wasn't told about when I initially purchased the shoe, I mean this is not fair we all know of the 7 day return policy why doesn't it apply here. So fine I was offered a voucher instead of cash, which is useless as I am not planning on setting foot in any of your stores ever. I am so upset this is just not good customer service at all. "