Hi,
If you purchased Windows Pro from the Microsoft Store, they normally won't send you a product key because your license is already tied to the Microsoft account used for the purchase.
Disconnect from the internet
Go to Settings > System > Activation. Click "Change product key," enter "VK7JG-NPHTM-C97JM-9MPGT-3V66T," and hit activate.
Reconnect to the internet and make sure you’re signed in with the Microsoft account you used for the purchase.
Restart your computer and check.