Hi, I am sorry to hear of the unlock not working with your fingerprints. Your phone's fingerprint sensor provides a convenient and secure way to unlock your phone, and keeps your personal information safe. If you are having trouble using your fingerprint sensor there are a few things to consider: https://www.samsung.com/us/support/troubleshooting/TSG01200322/
You can also see if a third-party application might be the culprit. The guide for Safe Mode is here: https://www.samsung.com/us/support/answer/ANS00062983/
Please let me know if this helps.