this 'problem' is very simple to fix:
1. write the new text in the text-object
2. wait 0,1 second (is a system action)
... the Wait-action is required because the text must rendered to get the 'new' size
3. text-object: set size to: width= Text.TextWidth + 10; height: Text.TextHeight + 10 (Text.TextHeight not Text.Height)
... if you don't add few pixels (in my code 10 pixels) it is possible that the objects height is not sufficient to display the second line
I wanted to add a project file for testing, but i don't see a button for it. But I hope you can still fix your problem.