Hello @GoTTiE ,
We apologize for inconvenience caused by not being able to use Samsung Keyboard. Please try suggestion from @userGqG3NLeNbO to clear data and cache of Samsung Keyboard app. If that doesn't resolve issue, we request you to capture issue with Samsung keyboard and then switch to Gboard to send us error report from the Samsung members app -> Beta Feedback -> Error Reports. A video recording along with logs would be extremely helpful in this scenario.
One Ui Beta Team