In short: if something cannot be delivered, the bats come back to your wallet by themselves. Items you have taken are final. No real money is taken, so there are no cash refunds. This is a summary; the full text below applies.
When a delivery fails
If an item cannot be delivered, the bats you paid for it are returned to your wallet by themselves, and the order shows as returned in your History. You do not have to ask.
Open orders
An order you have paid for but not taken yet is not lost: it waits in your /claim basket on the server it was bought for. Your Wallet lists your open orders.
Items you have taken
Once you have taken an item in game with /claim, the purchase is final. Items, ranks and kits are virtual goods; they cannot be returned or exchanged for bats or for money.
Wipes and expiry
Servers wipe on a schedule. Items you hold in game are lost at a wipe like everything else, and ranks end when their time is up. This is how the game works and is not a reason for a refund.
Something went wrong
If you paid and got something other than what the shop showed, or an order is stuck, contact us (Discord) and include your Steam name, what you bought and the order number. We will look into it and put it right.
Real money
No real money is taken at the moment, so there are no cash refunds. If real-money purchases ever open, the rules for refunds of those purchases will be added here before they start.