Settings are not saved or remembered.

Hi all, I have a problem where my Mac doesn't remember a lot of its settings.

It started with a non-remembering Dock in Mac OS 'Sonoma', I upgraded to 'Sequoia' in the hope that would fix it but it only got worse.

• The dock for example resets now to the Apple's default after relaunch. There is no longer a dock pref file associeted with my user profile after I read similar problems here and tried to reset the prefs file.
• System settings for the dock and spaces aren't remembered or not acted upon, like turning OFF the move to the top of your screen of an open window that blasts it into full screen mode.
• After each reboot the pop-up, "learn more about what's new" re-appears.
• Calendar keeps telling me "What's New in Calendar."
• I keep having to ok that certain newly installed apps show banners.
• I tried installing "Cocktail", it installs but closes immediately on opening. I created a new user and it installs and works just fine (I've deleted old 'Cocktail' prefs and files using 'Find Any File').
• I rebooted holding the powerbutton for a while and ran the disk utility repair disk.
• New installed apps key's (to verify I bought and own them) aren't saved.

I'm getting a bit desperate, as I ran out of idea's how to solve this.

Any help would be greatly appreciated.