Please perform the following steps to resolve the issue:
1- Run the device in Safe mode and reconfigure the fingerprint.
2- Make sure to use the central fingerprint parts evenly when you register or scan fingerprint, so that all portions of fingerprint, including the center and corners have been fully scanned.
3- If issue still persists, create data backup and reset the device.
For further assistance, register your concern in Samsung Members Application (Open Samsung Members Application > click on “+“icon > send feedback > error report/ask questions).
Team Samsung Members