If you lose your iPhone or Apple Watch, it’s best to erase all the credit card information from that device. While the Apple Pay feature is protected with biometric authentication and a preset password, it is almost impossible for a stranger to spend your money, but there is still a small risk when someone has access.
To be safe, you should turn off Apple Pay on any stolen or lost Apple devices.
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Method 1: Use the Find My app to turn off Apple Pay
If you have other Apple devices connected to the Find My app, you can use them to disable Apple Pay on a stolen or lost device.
• Start the Find My app.

• Select the lost device and scroll down to search for Mark As Lost. Click on Activate located below it to enable loss notification for the device. Finished click Continue to continue.
• Create a double 4-digit passcode to lock the stolen device. Then tap Enable in the upper right corner of the screen.
• In case you don’t have any other Apple devices, you can go to iCloud.com/find, sign in with your Apple ID and activate Lost Mode from there.

Once done, all cards added to Apple Pay on that device will be deleted. And don’t worry, you can still use the physical card. When you find your lost device, enter the four-digit passcode you created and Apple Pay will automatically be re-enabled.
Method 2: Use the Apple ID website to remove the card details
This option is the perfect solution if you want to remove your Apple Pay credit card from a specific device without activating Lost Mode.
• Go to appleid.apple.com and proceed to log in with your Apple ID.
• Next scroll down to see all devices using your Apple ID account.
• Tap on the device you want to remove your credit card from and click the Remove card link. In the confirmation window select Remove.

Once done, you will see Removal Pending status under the selected credit card. In a few minutes, your credit card will disappear from your device. Whenever you get your iPhone or Apple Watch returned to you, you’ll need to re-enter all of your credit card information.