A couple in the UK experienced a weird bug on their Samsung Galaxy S10 that allows bypassing the fingerprint reader to unlock the phone regardless of the biometric data registered in the device. The culprit seems to be the the the silicone case, which somehow confuses the reader and allows any fingerprint to unlock. Samsung has said that there is an internal investigation into this and recommended customers to use Samsung authorized accessories designed for Samsung products. Samsung-certified products are recommended for this. If a silicone case can indeed confuse the fingerprint sensor, crooks can easily slip one and try to unlock phone.
Source: https://www.bleepingcomputer.com/news/security/samsung-galaxy-s10-fingerprint-reader-defeated-by-silicone-case/