Hmm, not too much information, but one solution springs to mind as a firstie:
tap your windows key and type powercfg.cpl then hit enter
(This is the equivalent to clicking Settings->System->Power & Sleep->Additional Power Settings)
Once there, Click on Change settings that are currently unavailable
If the Turn on fast startup (Recommended) setting is not listed, then check Hibernate, click the Save changes button. Close the window and start over from the top.
Under Shutdown settings, uncheck Turn on fast startup (recommended), click the Save changes button. Close the window and restart you machine.
Now see if the machine will shut down like expected
I do think the setting is listed as it is known to cause your troubles from time to time. if it is not, and after you check Hibernate, the setting comes up unchecked, check Turn on fast startup (Recommended), resteart and then uncheck Turn on fast startup (Recommended) again
If it does not solve your challenge, tap your Windows key and type CMD right-click on the Command Prompt icon that appears and choose Run as administrator in the command window, type
Shutdown /s /f /t 10
This should shut down your windows after 10 seconds