Thank you for your feedback.
This is a known issue and a fix will be provided in the next SW update. In the meantime, please follow the steps below to resolve the issue:
To solve the problem of Object eraser not working, you need to delete apps related to Object eraser.
※ How to delete apps related to Object eraser
Settings -> Apps -> Search( Keyword : eraser)
1) Delete 'Object Eraser' app
2) Delete 'Reflection Eraser' app
3) Delete 'Shadow Eraser' app
We appreciate your contribution to the Beta Program.
One UI Beta Team