Dear Samsung Member,
Greetings from Samsung Customer Support!
In order to resolve your fingerprint issue kindly re-register the fingerprint:
Re-register the fingerprint by removing the already registered fingerprints: Settings > Bio metrics and security > Fingerprints > Continue > Set secure screen lock > Register your fingerprint > Tap Done when finished registering.
If the issue still persist, kindly send us log file through error report section in Samsung member application within 15 minutes of issue occurrence. (Samsung Members App > Feedback >Error report > Attach log file).
Thank you for writing to Samsung.
Samsung Customer Support