Applies: QuarkXPress 2019, Mac & Win

Background:

While creating a layout, single layout mode should not be checked. If it is an old document, it must be created in Single layout mode and that is why the layout gets grayed out.

Solution:
1. Open the same document whose layout you are trying to change.
2. Click on the Layout tab and click on new or duplicate to create another layout. 
3. Now you will find two layouts showing up.
4. Select the layout you wish to change, click on layout>>layout properties and change the layout name.