If you have a genuine Windows Pro licence, try this method to downgrade to Pro, then try activating that version with your product key.
Important - disconnect totally from the Internet
Open the Settings App (Gear icon on your Starr Menu)
Go to Update and Security - Activation
Click Change Product key
Enter this generic product key: VK7JG-NPHTM-C97JM-9MPGT-3V66T
When prompted, click 'Activate Product'
If the above does not work first time, restart your PC and try again.
Note the generic key will cause Pro for Workstations to downgrade to the Pro edition, then you can use your genuine Pro product key to activate Windows after you restart (not shut down) your PC