When you create or edit an iOS Restrictions profile, enter in your General tab requirements. Then scroll down on the left-side column and choose the Home Screen Layout (payload option). Select Configure. On the first page, you'll just see the Dock option to fill in. Select the Add Page button and this will give you the option to Add Folder on Page 1 (where you can also name the folder). You can continue to add pages and put folders on any page that you add. In the folder, you can then assign apps. In your case, start typing in ' Phone (Native, com.apple.mobilephone)' .
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