Technology

Something tells me you’re keylogged if you keep cancelling, ordering new ones and getting pwned within days of the new card arriving. Format your computers. Use more open source tools whose code you can audit. Firefox instead of Chrome, no sketchy extensions like Honey and cash back stuff. If you pirate stuff, try to do it from verified sources.

For one thing, stop using debit cards on the internet. Credit cards do not take the money out of your account first, thus offering you an additional layer of protection, and many like Discover in the USA are known for offering $0 liability for unauthorized purchases. They can be more of a hassle to use like they may call your mobile number to check on a suspicious purchase, but at this point it seems you want that level of paranoia. Don't miss a rent (or any important) payment bc you have nothing left in your debit account to work with! (Even if it is added back quickly, will it be handled quickly enough?)

As others have mentioned use a credit card instead of debit.

But if you need/want to use a debit card, then take a look at services like Revolut or Wise (non-referal links included).

Both provide you with debit cards that you can enable/disable instantly within their app. Revolut gives you "virtual cards" which can be used for online subscription, so you can create a dedicated virtual card for each subscription (minimizing the impact if/when one of your cards is leaked). Revolut also has "one time use cards", so a new debit card number for a single purchase. In practice, more and more vendors are disallowing "one time use cards", but you can create a similar effect with the virtual cards.

Both platforms also allow you to set up dedicated (monthly) spending limits on either the physical or virtual cards. So you can limit your exposure that way too.

A shop you both go to has a machine with a fake overlay swiping your info. You can find online how to spot those. I doubt it's happening online.

As noted elsewhere, do everything you can to avoid handing your card to anyone.

Use tap to pay wherever possible, then chip - neither of those methods give the card number to the merchant. Do not swipe unless you absolutely have to, and then inspect what you are swiping to make sure nothing is attached to the card reader.

For online purchases, do everything you can to avoid giving your card number to anyone - use ApplePay / GooglePay / Amazon Pay / PayPal etc. wherever possible. These can be used to put charges on your card without giving your card # to the merchant. These are one-time authorizations (unless you explicitly identify it as a subscription / recurring charge), so they can't reuse the transaction token they get.

Credit and debit cards are not as secure as banks pretend them to be. Chips can be cloned with a cheap device sold in the black market (this is known as "skimming"). PINs can be easily stolen simply by eavesdropping.

My personal opinion: A business you frequent has been constantly skimming credit and debit cards. If you give your card to any salesperson and lose sight of it, the probability of it getting skimmed is pretty high.

NEVER give out your card. Ask for the salespeople to give you the terminal and scan it yourself.

Other than that, change your passwords, and NEVER reuse them.

EDIT: As others have said, NEVER EVER use your debit cards on the internet. Ask if your credit card company provides virtual credit cards (which require you to use a phone app to authorize every transaction). If not, choose another company.

Have you used these cards in public? Your information could have been picked up by card skimmer.

At least where I live, it's very common to hand payment cards over to wait staff at restaurants. I had my card information compromised during a visit to Boston several years ago.

What’s your wifi situation like? Is your network secure? Are you often using a shared or public network? Perhaps it’s time to change your wifi password or look into a vpn if you are often using public networks. This is all on top of the usual changing your passwords, setting up two factor authentication (not via sms, use an Authenticator app) etc. you could also consider a service like Privacy (card number generators with limits or one time use)

You said you use your credit card on Facebook and you're not sure why it's getting stolen .....🙄🤔

Look for common patterns, are there places you both regularly use your cards? Look at those places. Sometimes even your bank can be compromised.

If you are financially able, use a credit card instead of a debit card. I do realize that only makes sense if you are able to pay it off every month, and when we were younger that was impossible. But maybe get one to only use online?

Interesting.

Does it concern the cards from the same bank? I've read about some banks actually abusing their own clients and meddling with their money...

Get some new cards to start with.

Make an account in a bank/service that lets you generate and use single-use cards. Revolut comes to mind (I have a referral code too, wink wink), people also use a service I forgot the name of. Privacy-something. They used to sponsor a lot lf YTubers, but now I use SponsorBlock so I don't remember.