According to Nintendo’s official website, Netflix is no longer available for new users to download on both 3DS and Wii U and will be shutting down service on these platforms on June 30.
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Starting Dec 31st, 2020, the Netflix app will no longer be available for new users to download from Nintendo eShop on the Wii U console or Nintendo 3DS family of systems. During that time, it will be possible for existing users to re-download these applications. Service for existing users will continue until June 30th, 2021. Thank you to everyone who enjoyed Netflix on these platforms over the years.