Calibration isn't just a button press. It often requires specific optical calibration blocks (yellow or black rubber pieces) to provide the sensor with a "perfect" reference image.
The Samsung Fingerprint Calibration Tool is a vital utility for re-syncing biometric sensors after screen repairs, addressing the "Fingerprint sensor calibration needed" error. Methods include the official Self Repair Assistant app, specialized physical jigs (GH81-25050A), or diagnostic menu resets, with success often depending on using high-quality display parts. For official troubleshooting steps, visit Samsung Support samsungparts samsung fingerprint calibration tool