Order cancelled with no reason - Customer service doesn't get back to you.

I placed an order with OneCart, the order was cancelled with no reason given. I did contact customer service, who said they would investigate and get back to me. 4 days later, and that hasn't happened. I have requested a refund, as they store the amount paid in a "wallet" and you have to request it from them, so let's see if it comes through in 2-3 days.