We're sorry we refunded you when you wanted a replacement item!
The most likely reason for this would be if we didn't have the new size you wanted in stock. We always do our best to process exchanges where possible, but sometimes, like in sale periods, we might be out of stock for the exact item you're after. If this is the case we'll refund you, and we would always email and let you know - it's worth checking your inbox for a message from us in these cases.
If you're still unsure, then drop us an email to email@example.com.