To activate Twitch Tv on Xbox one you need to visit the url - https://account.microsoft.com/account and follow the give instructions to sign in with your Microsoft account. After login into your Microsoft account, follow the given step below -
1. At the top of the page, choose "Activate a code" from the menu.
2. Now, select "Redeem Code", and a verification code will be sent to your email.
3. Enter the code and tap on "Apply".
4. Now you'll see a message letting you know that you have successfully activated Twitch tv on Xbox one.

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