Text tool creative warp grayed out and does not function.

Perhaps I'm not understanding how the type tool's creative warp tool is supposed to work. It seems to work if I apply the desired effect when I first type in the text. However, when I leave the text tool and return to do more edits, the warp tool no longer will work. I have reset the preferences to no avail. I've even uninstalled and reinstalled Photoshop making sure I did not transfer any old preferences or plug-ins. Still, the same result.  ??