Can you go to your Windows Settings > Accounts > Access Work or School (note, it is the briefcase icon, not the envelope icon). Then see if the organization email address is still listed? If so, click on it and then disconnect it.
Restart the computer. That should get rid of the org account.
I will explain how this happened. You probably have used an org account to log into apps like Teams, or Msft 365 apps. When you signed in then, it would ask if you want to allow org to access settings, and you should have clicked on "sign into this app only" instead of allowing it. When you allow it, what it means is you also enrolled your device into intune device management in your org. Your IT can push group policies to regulate your device, doesn't mean they can see your data, but they can enforce stricter security rules, such as requiring stronger PIN, setting PIN expiration, making sure security update is not stalled, etc.