When you report fraudulent or unauthorized use you need to contact the issuing bank, not Visa or Mastercard Inc. They are the ones to reverse fraudulent charges. They should cancel the existing card and issue you a new one (with a new account number, of course). Otherwise an unauthorized person could continue to use the card number and you'd have to keep dealing with it. It would surprise me if they don't automatically tell you that they will issue a new card but if they don't, you should request it.
This has happened to me a couple of times with different card issuers and each time a new account number was assigned. Of course, if you have any automatic payments tied to the affected account or if any websites have your credit card number saved in order to facilitate purchases, you will have to make the necessary updates.
Contacting my bank is exactly what I did. I was attempting to clarify what
@Darth Shiv said as I was allowing for the possibility of a different experience that Darth Shiv encountered. I don't know everything.
Trust me, I know how to report credit card fraud. That route did bring refunding the charges - technically - LA Fitness refunded them, since, I also contacted LA Fitness as the card was used fraudulently. At that time, LA Fitness did not care that I told them that the person using my card was not authorized to use it and continued to charge the card anyway, even though it was LA Fitness that refunded the card. You might wonder how - read on.
Incidentally, for those who are unaware, and in case something like this happens to them, there is a "feature" of credit card use that vendors, when they enroll you for a membership, can select that says "if there are any changes to this credit card account, give us the new number, expiration date, etc." Which, at the time, LA Fitness did and that is why, even though I had told them that that the dude using my card was using it fraudulently, LA Fitness continued to charge my card. Because of this feature, they were able to get the new number my bank had given me after I reported the fraud and my bank issued the new card/number, and LA Fitness continued to charge my card.
This kept happening until I was able to talk to the "right representative" at my bank who knew how to block, permanently, LA Fitness from ever again charging this credit card account. Maybe someone else might find this information useful, that you can request your credit card bank to permanently block any merchant from charging your credit card if there is a need to do so, and in my case, there was an obvious need.
I also contacted the Secret Service since they investigate credit card fraud in the US, and they basically said that since it was below the $1K threshold, they were not going to investigate even though I had the perp's name.
You should try this new tool called Google:
"Five Different Ways to Cancel Your LA Fitness membership"
It includes mail, email, web, phone, and in-person cancellation.
Ah, your typical snark. Your reply is irrelevant since it was not MY ACCOUNT which I mentioned in my post. It was the account of a "member" fraudulently using my card, I should never have had to "cancel" the account. It was not mine. Especially so, I should not have had to go to the lengths that I did since I informed LA Fitness that the "member" was not authorized to use my card and was using it fraudulently. Maybe people can use your fabulous new tool called Google and, IMO, likely because of numerous complaints against LA Fitness, LA Fitness will cancel accounts without the extreme lengths cancelling an LA Fitness account used to require.