If your payment is not successful, your order shall be pending in our system and won't be processed. You can revive your order by going to your My Account area and click on Reorder option next to your previous pending order.
If you have used your store credit in your order where payment wasn't successful, your store credit would get replenished automatically after canceling your order. In case you don't see your store credit back in your account, please send us an email, we'd be happy to assist you.