Customers who have a credit card have the right to dispute transactions directly with their card-issuing bank using established and standardized processes. This approach helps to ensure that complaints are handled efficiently and according to internationally established rules.
Another reason why you may not be contacted directly by your customers is that credit cards are used worldwide. Language barriers and different time zones can make direct communication and handling of complaints difficult.
It is also possible that people who initiate a chargeback because they claim to have unauthorized transactions in your business are not actually direct customers of your business, but have been victims of card fraud. In such cases, contact is usually made via the card-issuing bank to resolve the matter.