Hello, I'm Wes, and I'll be assisting you today.
Sometimes the error message saying that you already redeemed the subscription will display if you are trying to use the same account for an existing trial of office 365.
Log into www.office.com/myaccount website using the subscribed email account and check if any trial subscription is associated with the same account.
You may either have to cancel the Office 365 trial subscription and then try redeeming Office 365 Personal or create a new Microsoft account and associate the new account to the Office 365 Personal.
To Cancel the initial subscription, follow the steps in this link: https://support.office.com/en-us/article/Cancel-Office-365-for-home-d219b5a5-9443-44cf-bcfa-80a052bdd18c?CorrelationId=9d19d3fa-330a-4913-bf98-46ae59e67e31&ui=en-US&rs=en-US&ad=US
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