Area code is for phone. Zip code is for postal address.
I suspect this question relates to reception of local channels via one or another of the channel apps. If so, this is something either set manually in the particular channel app, or the app uses the location indicated by the IP (Internet Protocol) number assigned to your internet connection by your internet supplier.
You can can check where your IP indicates you are located by going to any of several websites that report this info back to you, such as https://www.iplocation.net/. If this doesn't represent your actual area, contact your internet provider and ask to be reassigned an IP in your area.
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I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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