Cannot find component: Screen 2


I’m using app inventor 2. I have a back up of an app from app inventor 1 and tried to update it on ai2. for some reason it says now “Cannot find component: Screen 2” although I didn’t change anything and there is a “Screen 2” - any thought on what I should do?
(The same thing happens with all the screens)

Thanks in advance

this is the Thunkable forum…
it is sufficient to ask in the MIT App Inventor forum…