https://wccftech.com/one-ui-2-0-beta-reportedly-locks-some-galaxy-s10-users-out-of-their-phone/

The Android 10-based One UI 2.0 beta, unveiled by Samsung a few weeks ago, has since expanded to the Galaxy Note 10 series. However, some Galaxy S10 users are experiencing what could be a critical bug in the software. Their devices are reportedly locking people out by refusing to accept their PIN, password, or pattern. Several users have taken to forums such as Samsung Community and XDA Developers.

The problem crops up after a device reboot, and the only way to unlock it is via Samsung's Remote Unlock feature enabled on Samsung’s Find My Mobile service, which lets you disable all form of authentication (biometric and otherwise.) This gives rise to another problem that there is no solution for—there is no way to set a new PIN/pattern/password after successfully getting back into your device. Since the device doesn't recognize the old PIN, there's no way for one to change it, as the process involves inputting said data.