Running High Sierra 10.13.6 but Software Update wants to install the same OS update

UPDATE

Found another post with the following instructions and it solved my problem.

After trying just about every solution I could find I was able to resolve the problem. I also noticed that Spotlight was not working as expected. Typing Disk for example did not find the Disk Utility APP - just web search links. It was my suspicion that something was cached that could not complete somehow and this held up a shutdown? I found some instructions to use Command Line instructions to clear. After running these my MBP was able to shutdown/restart. Following this (just for truing up) I installed the 10.13.6 combo update. All is well now.

Here is what I did (from How to fix a Mac that won’t shut down)

After opening terminal, type all the following commands in the window, one-by-one in execution.

1. rm -rf ~/Library/Caches/*
2. rm -rf ~/Library/Saved\ Application\ State/*
3. sudo rm -rf /Library/Caches/*
4. sudo rm -rf /System/Library/Caches/*
5. atsutil databases -removeUser
6. sudo atsutil databases -remove
7. sudo atsutil server -shutdown
8. sudo atsutil server -ping
9. sudo rm -rf /var/folders/*

Once you performed the last line, restart your Mac.

Following this the shutdown happened. The Spotlight rebuilt and now works as before. Seems like I have been able to save wiping SSD, reinstall and restore! As always your milage may vary.

I tried twice and keep getting the black screen and cursor.

So, I restarted and left for work at 5:30 this morning. Got home at 4:00 and still had the black screen and cursor. There has to be something wrong.

I did, also reset PRAM as well as started in single user mode the same thing happens.

1TB Fusion

Will that trash my stuff? Settings and what not?

Yes it runs fine, just can't update. It's bizarre, I tried to update to Mojave and the same thing happened. I had a ton of trouble then had to restore from Time Machine.

No