I feel the fingerprint recognition rate became low after software update.

The fingerprint recognition was improved through this update. Because attaching the protective glass or thick screen protector may decrease fingerprint recognition rate, we recommend to use a genuine protective film by Samsung. 

When you scan fingerprints on the device with ultrasonic fingerprint sensor, be aware of the following common conditions that may affect the feature’s performance:

•  Ensure that the screen protector or the touchscreen on the fingerprint recognition sensor area is not scratched or damaged by objects, such as coins, keys, pens, and necklaces. 

• If protective film/screen protector is dirty or scratched, please replace with a new one and we recommend that you register your fingerprint again for better fingerprint recognition rate after replacing the protective film.

• Ensure that the fingerprint recognition sensor area at the bottom center of the screen and your fingers are clean and dry.

• The device may not recognize fingerprints when the screen protector/protective film is not attached nicely and tightly on the device screen. Air gaps or foreign substances between the protective film and screen may decrease the fingerprint recognition rate. 

• If you bend your finger or use a fingertip, the device may not recognize your entire Fingerprints (which it needs to). Press the screen so that your fingertip spreads over the wide surface of the fingerprint recognition area.

• If you remove the protective film or attach a new one, we recommend that you re-register a new fingerprint.

• The device may not recognize fingerprints from fingers that are too dry, especially when you wake up in the morning or for those who have drier skin types than normal, or when you’re outside in winter or in low humidity conditions. We recommend that you moisten your finger using hand cream and try again. Samsung is committed to   continuously improving fingerprint recognition rate so we always encourage users to keep software and apps updated to the latest version.