Your product has limited stock available, more customers than stock bought it at the same time.
Most of them got the invoice completed but some received an error and the invoice was voided. They're now frantically trying to contact you: Where is my product? Where is my money?
How to handle it
First of all, the money is not gone. It's either been sent back to the customer already or will soon be paid out to you, it all depends on the type of gateway used.
Unfortunately, refunds do not exist through blockchains.
Once a transaction is sent and confirmed you cannot go back, it is now on our wallets when the customer tried to buy your product.
To solve this, we queue the invoice (even if its status is CANCELLED) for the next payout, which will happen based on the cryptocurrency that was used with the following options available:
Scheduled payouts at the end of the day
Instant payouts within hours of the invoice being voided
Platform payouts within the next 48 hours
Once you receive the next payout, the voided invoice funds will be with you and you can decide whether or not to provide your customer with new stock or a refund out of your wallet.
PayPal and Stripe
We automatically refund Credit Card, Bank and PayPal transactions to the customer if the product purchased was out of stock.
You do not have to do anything else in this situation, just inform your customer that he should have the full amount back within a few hours or days (based on the financial institution's policy).
Refunds are not supported through their APIs, meaning that the funds are now on your wallet (immediately available) and you can decide how to proceed.