Hi, I'm John! I will help you with this.
Yes, having Microsoft 365 Basic on the same account can sometimes cause conflicts when you try to redeem or activate a Microsoft 365 Family product key.
Let’s check a few things first:
Please sign in to https://account.microsoft.com/services and see: Is Microsoft 365 Basic still active? Does Microsoft 365 Family already appear there?
Try redeeming the product key here: https://redeem.microsoft.com Make sure you are signed in with the correct Microsoft account.
If Basic is active, try turning off auto-renew or cancel it first, then try redeeming the Family key again.
If you already redeemed the key before, the “token not found” error may mean it is linked to another account.
To help narrow down the issue:
- Did you buy the Family plan from Microsoft, a store, or online?
- Are you using the same Microsoft account where Basic is active?
- Do you see any subscription listed on your Services page?
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Regards,
John J.D.