Cumulative Update for Windows 11 (KB5033375) repeatedly fails to install (0x80070002)

Hi everyone. First time poster here and hoping someone more knowledgeable can help.
I recently built a new PC and installed a fresh Windows 11 pro. Everything's been fine and it runs really nicely but ever since first build over a month ago I have had it abjectly refuse to install KB5033375 with the Install error code 0x80070002.

I have tried all the steps I can find anywhere on the internet so far - resetting windows update, renaming various folders in the Windows directory, manually downloading from the catalogue to install, following all the (hundreds) of suggested commands on the official Microsoft Help page. Nothing is working. I've even tried manually installing 23H2 KB5027397, which seems to have worked and shows in my Update History but isn't showing in winver...

I go to install it. It says I need to restart. I hit restart. It gets to 2% on shutting down, restarts, gets back to 2% then says "oops, something went wrong" and I'm back where I started.

Does anyone have any suggestions at all that might help? It's really frustrating because even just trying to ignore it causes Windows update to decide that I have delayed it for long enough and just hard reset my PC even when it's in use to try again...

Getting desperate now. Any thoughts or ideas? Thanks a lot!

I would get an ISO from MS site, the current one contains the latest build 22631.2861.

Use this to perform a repair install

Welcome to the forum.

Here's what I would try and the order I would try it before doing a repair install.

1. Make sure you have no corrupt system files. Open a command prompt as administrator and type sfc /scannow
Pay attention to the scan results to see if SFC found anything it could not repair. If it found corruption it could not fix followup with this command (note the spaces)
dism /online /cleanup-image /restorehealth
Restart computer
I would run troubleshooter-settings-system-troubleshoot-other troubleshooters-windows update-RUN.

2. Disable all third party AV apps, including Malwarebytes. Using task manager, make sure they are not not running in the background.

3. Reset Windows update using Brink's tutorial Reset Windows Update in Windows 11 Tutorial

4. CLEAN UP COMPONENT STORE - dism /online /cleanup-image /startcomponentcleanup
referenced here.
Analyze and Clean Up Component Store (WinSxS folder) in Windows 11 Tutorial
Restart.

Try windows update again. If it still fails then do a repair install. Repair Install Windows 11 with an In-place Upgrade Tutorial

Good luck.