Superbalist Bad Quality and Customer Service

I bought the light up pink sneaker from Superbalist in June. First of all the size was to small, which they exchanged for a bigger size. My niece wore it a few times then the straps broke. Its not even a month and this happens. She was so excited about these sneakers but @Superbalist.com sent the sneakers back saying its not in a sellable condition. Who buys sneakers to last a few weeks... I'm extremely upset because clearly its a quality issue as its not supposed to be breaking. Now I have a very upset little niece. They refuse to replace or refund my money.