Custom field groups displaying on all post type but I only want it being displayed on one.
Solution:
To resolve this please follow the instructions below:
1. Go to Toolset -> Custom Fields
2. Edit your custom field group.
3. Under Settings for XYZ click edit under the 'appears on' section.
4. Select the custom post type you want to allow this field group to appear on. Then hit apply.
5. Save your custom field group.