For the issue, it seems that you need to reactivate the system.
Based on the current situation, I would like to suggest you to contact Microsoft Product Activation Center by telephone to verify the product key and activate your system.
To start the Product Activation Wizard, follow these steps:
1. At the Start screen, swipe in from the right side, or hover your mouse in the upper-right corner of the screen to display the charms menu.
2. Tap or click the Settings charm.
3. Tap or click Change PC Settings.
4. If your PC is not activated, PC Settings will provide instructions that are customized to your activation error. If telephone support can provide help for your error, tap or click the appropriate link, which may resemble one of the following:
b. Activate by phone
c. Contact customer support for help
For the detail information, refer to the following link:
How to contact a Microsoft Product Activation Center by telephone:
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