Preview doesnt show up

I want to add a small battery indicator to the lock screen of my Samsung galaxy phone via Samsung’s LockStar app. When I try to edit the widget in the app, there is no preview and it gives the error below. Even if I press the save button on the top right, the widget is not saved. Can you help me?

I deleted the app data, removed the widgets and added widgets again and the problem was fixed

This was a known issue in one of the previous beta versions. To stop this from happening again, make sure to get the latest beta from the link below.