Have you checked your internet connection status? All is working fine on mine, and i had no issues with the update itself from my end, However, it may be that the download for the update got interrupted, so just needs restarting. If you go into the downloads section via the settings menu on the switch itself, it should have a button that lets you restart any paused downloads. (never had to do it on the switch yet, but that's how it worked on the WiiU, so admittedly I'm guessing it'll be the same) but certainly that's what I'd be trying first.
Hopefully that will work, but if after doing that you find you still have issues, get back to me, as there may still be other things you can try. But see how you get on with that one first, and we'll take it from there.