I have run into this more than once. When naming labels I have accidentally used the same name as another label. I see a small error message that says "Name already exists" then the label name reverts back to a default or previous name.
Is there a more efficient way to track these down and fix them than clicking on all the labels in all the pages, like some sort of search? Or is there a procedure to debug the project (Not the app in the browser which wouldn't help here)?
Thanks!