Received message to upgrade and it's been stuck in the working on it screen for hours. What should I do?

[Windows Central Question]

Received message to upgrade and it's been stuck in the "working on it" screen for hours.

I have tried rebooting several times, and it still gets no further than "working on it." How long should I wait as it says 10 seconds should be the wait time? I've seen dozens of postings asking this same question, but no response or reply to help us.