https://wccftech.com/latest-galaxy-s21-one-ui-4-0-beta-brings-lots-of-bug-fixes/

Samsung has gone ahead and released another One UI 4.0 beta update for the Galaxy S21 series after what I thought would be the last beta update for the phone before the final release. Today's beta update brings a heap of bug fixes as well as improvements. These changes and fixes show that Samsung is on track to release the stable version by year-end.

All the countries where the beta program is currently in progress are getting the update, and the firmware version this time around is ZUK1. If you are using the Galaxy S21 device, you can update to the latest beta by heading to Settings > Software update menu. Remember, only those who are running the One UI 4.0 beta will be getting the update.