For home or personal use, you can choose from two Microsoft 365 subscriptions: Microsoft 365 Family or Microsoft 365 Personal. However, your Microsoft account — the email address and password you use to install Office — can have only one active Microsoft 365 subscription.
If you add the same Microsoft 365 subscription to your Microsoft account, you’ll have the same subscription benefits (same number of Microsoft 365 devices you can sign in to and the same amount of Skype minutes and OneDrive storage) as before. You\’re extending the amount of time for that subscription, not increasing the number of Microsoft 365 devices you can sign in to or amount of online storage you get. You can extend the duration of a Microsoft 365 subscription for up to 5 years.