Chargebacks and inquiries
If you accept credit cards on your store, then it's likely you need to deal with chargebacks or inquiries. When a cardholder has an issue with a charge on their credit card, they can contact their bank to dispute the charge. The bank then makes a chargeback or inquiry. The cardholder can be one of your customers or someone who believes that their card was used on your store without their permission.
If the cardholder's bank makes a chargeback, then the bank takes the disputed amount from you right away. The cardholder's bank also takes a chargeback fee from you. If the cardholder's bank makes an inquiry, then they don't take the disputed amount or a fee right away.
You can try to resolve the chargeback or inquiry in a few ways. Often, the company that issued the cardholder's credit card reviews any evidence, and then resolves the chargeback in either your favor or the cardholder's favor. If you win the chargeback, then you get the disputed amount back, and Shopify might refund the chargeback fee depending on your country or region. If the cardholder wins the chargeback, then the disputed amount is returned to the cardholder.
If you're using Shopify Payments and you're issued a chargeback, then the amount is deducted from your next available payout.