# 4.Common Issues

The KeyPal Card is a card-sized device that uses NFC technology to backup mnemonics and supports blockchain signatures.

To use the KeyPal Card, please enable the NFC function on your phone (use a phone that supports NFC functionality; some phones, such as the HUAWEI Mate 60, have NFC deficiencies that may prevent the card from functioning properly).

**NFC Sensitivity Issues:**

* The NFC sensing area on most phones is located near the camera.
* For iPhones, the sensing area is also near the earpiece.
* If the card is not being detected, slightly move the card to different positions.

When the card is close to the phone's NFC area, the phone system will indicate that the card has been detected, confirming that the card is ready for use.

The card is reusable and supports up to 500,000 data write cycles. To backup new mnemonics, simply repeat the backup process to overwrite the existing data.

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