Hi there.
Sorry for the inconvenience caused to you
Based upon the query
Open Command Prompt
c:\windows\system32\slmgr.vbs /ipk PRODUCT_KEY
hit ENTER
Sample: c:\windows\system32\slmgr.vbs /ipk 12345-12345-12345-12345-12345
Check if the key is working there.
Please check if there is any error code available. Please check if the internet connectivity is good enough and the pc is connected with it.
And see if it helps,
Thank you
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