Cleaning the Touch ID sensor
A clean Touch ID sensor can read your fingerprint more easily. As needed, use a clean, lint-free cloth to wipe off any dirt or debris from the Home button.
Troubleshooting Touch ID
1. Ensure that your fingers and the Home button are clean and dry.*
2. Note: Cover the Home button completely. Don't tap too quickly, don't press down hard, and don't move your finger while Touch ID is scanning.
3. Tap Settings > General > Passcode & Fingerprint > Fingerprints and verify:
One or more fingerprints have been enrolled.
4. If one finger isn't working, tap Edit in Settings > General > Passcode & Fingerprint > Fingerprints > Edit to delete and then re-enrol the finger.
5. If that finger still isn't working, try enrolling a different finger.
6. If you are unable to complete Touch ID registration in iOS Setup Assistant, restart your iPhone 5s.
*Moisture, lotions, sweat, oils, cuts or dry skin may affect fingerprint recognition. Certain activities can also temporarily affect fingerprint recognition, including exercising, showering, swimming, cooking, or other conditions or changes that affect your fingerprint.