How do I update Sierra to Catalina

I am trying to get my machine to update from Sierra to Catalina in my virtualbox windows machine but for some reason or another, whenever I try to update, the installer will go through, then it will restart but it never does anything. It just simply restarts the computer and the update doesn't go through. I log in and it takes me back to the desktop as if nothing happened. No update or anything. What is going on?

submitted by /u/Skynet0928
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