This is not considered fraud. You are voluntarily repaying someone else's credit card. If there is an agreement between you, the other party has breached the contract and can go to court based on the agreement. If there is no agreement but only a verbal agreement, this situation will be difficult to obtain evidence and difficult to handle.

Credit card fraud (also called credit card fraud) refers to the act of using credit cards to conduct fraudulent activities for the purpose of illegal possession, in violation of credit card management regulations, and to defraud a large amount of property. This crime can only be subjectively constituted intentionally and must have the purpose of illegally possessing public or private property. If the perpetrator does not intend to commit fraud, even if he obtains property in violation of relevant credit card management regulations, he cannot be punished as a crime. If you use a credit card without knowing it is a forgery or invalid, make an overdraft in good faith, misuse another person's credit card, etc., you will not be punished as a crime.