Hi LORENA perez,
I understand how frustrating it is to pay a significant amount for a Windows license, but seemingly lost it just by reinstalling Windows on the same PC. Based on your description and similar cases, the most likely cause is that the reinstallation changed the hardware identification that Microsoft's activation servers see, even though it is physically the same computer.
Before getting further, just to make sure we're on the same page, I'd like to ask whether the Windows 11 product sold directly by Microsoft on Amazon, or by a third-party seller? In addition, what exactly is the Windows edition that was suggested by Gigabyte? Those details might affect the length of support that can be provided by Microsoft for your license.
In the meantime, you can check out the following to see if they can improve your situation.:
1 - Run the Activation Troubleshooter
- Open Settings > System > Activation > click Troubleshoot
- If prompted, click I changed hardware on this device recently
- Choose this device from the list (if available) and attempt reactivation.
2 - Try the Microsoft product self-activation portal
- Sign into https://visualsupport.microsoft.com/ (captcha)
- Choose Activate a Microsoft Product > Windows > Windows 11
- Enter Installation ID (find by clicking Help me find Installation ID)
- Follow the onscreen instructions to attempt activating Windows license.
3 - Contact Microsoft Support
- If the Troubleshoot (step 1) fails, click Contact Support at bottom of Get Help window.
- Or you can sign into Contact Us - Microsoft Support:
- Enter your issue > click Get Help
- Scroll to the bottom > click Contact Support
- Choose a relevant category > Continue > select chat option.
- If you don't see it, go back and change to another category.
Note: The support contact team only works at certain times, so if the last window shows that it's unavailable, try opening it again the next day. If you prefer phone support, you can leave a phone number. This way, they can call you and help you.
I wish I could provide more direct help, but Microsoft Q&A is just a user-to-user support community. If the key was genuinely purchased from Amazon and only ever used on this PC, the Support team is the only one that can verify the license and manually assist.
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