When you upgrade from a Microsoft 365 Personal subscription to a Family subscription, the charges may not automatically adjust for the time remaining on your Personal subscription. Typically, when you make such a change, you are charged the full price for the new subscription, and any adjustments for the previous subscription may not be reflected immediately. This can happen because the billing system treats the upgrade as a new purchase rather than a continuation of the existing subscription.
To resolve this issue, you should contact Microsoft 365 Support for assistance. They can provide specific details about your billing situation and help you understand if any adjustments can be made for the unused portion of your Personal subscription.
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