The same happened to me too.
I was travelling and the signal was weak. After 3 tries my Note 9 told me that it couldn't finish the update.
It is stuck ever since.
Tried emptying the cache partition in recovery mode, doesn't work.
I also tried to delete cache and other data of the Software Update app. That does not work either.
I would really appreciate any feedback from Samsung...
Samsung customer service just helped me solve this issue!
Download the Samsung Smart Switch to your Mac or PC. Connect your phone via USB and it will automatically recognize your update.
I had to restart my phone one more time to debug it, and the program was able to finish the update for the second try.
I had the same problem with the 1st of October update, downloaded the Smart Switch software to my laptop connected it via USB and it instantly download my new update. Thank you DanAnty...
And what happens if you don't have a pc? I only have my phone and it won't download update, it's doing exactly what is described above. I have a samsung s9 note