I have recreated this and it seems to be changing the Tab Navigation Options because when I set the label to the object it has updated.
The problem is the screen titles at the top don’t update. It’s as if the Navigation Options do change, but the screen titles aren’t called to be updated.
Here’s the settings I have. On the Design Page you’ll see I have red squares drawn around the x
If you click the x it causes it to show “undefined” in the little text box to the left of the x
If you click in the text box it displays “Empty string” in the text box as you see in my screenshot
Very bottom screenshot is my result on the Thunkable Live app
There’s another thread about this here where it seems some people have success & others do not. Idk what is causing the discrepancy is either.