Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
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I understand that you are experiencing the issue with signing in Volume Licensing Service Center.
However, Microsoft has been migrating most Volume Licensing Service Center (VLSC) functions into the Microsoft 365 Admin Center to make everything more unified. That means downloads, product keys, and agreement info are now usually found here
In the meantime, if you are the IT admin:
-Please sign in at admin.microsoft.com with your organization account
-Go to Billing > Your products > look for Volume Licensing tab.
-If it is still missing, search “Volume Licensing” in the top search bar.
Note: If you’re an end-user and unsure who the IT Admin is within your organization, you can find guidance on locating them here: How do I find my Microsoft 365 admin? - Microsoft Support.
This initial response may not fully address everything you need, but it should help me better understand your situation. Please check and let me know what you find so I can investigate further if needed.
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