I have what is probably a related problem, in that my half dozen Shutdown methods do not work. I usually have to run a couple or me before Shutdown, if I don’t want to use the power button (which does work). This must be a Windows nota Cube hardware problem and because I have some other issues (eg.no Store) I am going to do a repair reset so hope it will clear them up. Do you try a variety of Shutdown methods, including Sign out which works more often? In addition to the two methods accessed by the Ctrl Alt Del combination, and those in the WinX menu I have 3 different desktop shortcuts. All work slightly differently, so one may work when others do not. I can provide some detail if you want, plus a link to an article on various ways to Shutdown.
Someone else may post more straightforward advice.
I too have used Switch to Android for this and some other Windows problems.
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