Hi #lavish, this does seem to be an issue caused by the 1803 update, a lot of users are reporting this over the last few days . . .
Click the link below to download a small utility which will find your Windows 10 Product Key
http://neosmart.net/OemKey/
Go to Settings - Update and Security - Activation
Try entering that product key there to activate Windows
Otherwise, have that product key at hand and contact Microsoft Support and ask them to help you re-activate your Windows 10
Choose a local Phone Number:
https://support.microsoft.com/en-us/help/13948/...
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