Need to auto add area code to 7 digit dialing

[Faceplant15]

My phone, Note 5, used to auto add my area code to my 7 digit dialing with Marshmallow. With Nougat it does not auto insert my area code and I am not able to locate the place to enable this. Can someone let me know where this setting is? I've been through the Settings area in the phone app, nothing in there that I can see.

Thanks for any help!