Microsoft account page keeps refreshing when I try to extend a subscription

Hello @Christopher Bedford

Given everything you've already tested: different browsers, private mode, cleared cookies/cache, another computer, another ISP, password reset and 2FA, I don't think this is a normal browser or Windows issue.

The repeated redirects between account.microsoft.com/services, login.live.com and account.microsoft.com/auth/complete-client-signin suggest the Microsoft account authentication/session isn't completing correctly for the Services & subscriptions page.

The good news is that since you've already purchased a Microsoft 365 renewal key, you don't actually need to access the Services & subscriptions page first to redeem it.

Go directly to:

Microsoft 365 setup and product-key redemption: https://setup.office.com/?source=microsoft365?

Sign in with the same Microsoft account currently associated with your Microsoft 365 subscription, then enter the 25-character key. Microsoft specifically documents this method for extending an existing Microsoft 365 subscription.

If successful, the additional subscription time should be added to the existing subscription. Microsoft allows subscription time to be extended up to a maximum of five years.

I would not redeem the key against another Microsoft account as a workaround, because the key becomes associated with the account used during redemption.

If microsoft365.com/setup also enters the same authentication loop, then this is strong evidence of an account-side authentication/subscription issue. At that point I'd contact Microsoft Support and specifically report that the failure reproduces across devices, browsers and networks and occurs during the complete-client-signin flow. Microsoft recommends contacting Support for technical problems managing or renewing a Microsoft 365 subscription.

You can also try the alternate redemption endpoint:

Microsoft Redeem: https://account.microsoft.com/billing/redeem?

Microsoft specifically recommends that endpoint when normal Office/Microsoft 365 product-key redemption isn't working.

Sharing you the references:

Microsoft – How to renew Microsoft 365: https://support.microsoft.com/en-US/accounts-billing/subscriptions/how-to-renew-your-microsoft-365-subscription?

Microsoft – Where to enter your Office/Microsoft 365 product key: https://support.microsoft.com/en-us/microsoft-365-activation-licensing/office-install/where-to-enter-your-office-product-key?

Microsoft – Problems renewing Microsoft 365: https://support.microsoft.com/en-us/accounts-billing/subscriptions/problems-renewing-a-microsoft-365-subscription?

If both direct redemption URLs produce the same redirect loop, please post the exact error shown there (without personal information). That would help confirm whether the problem is specifically with the account authentication flow rather than the subscription itself.

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