Unable to login to Icloud
I get a message, I cloud Preferences wants to make changes to your account.Type your password to allow.
Username is greyed out and shows system username but doesn't accept admin password. I had reinstalled OS after which unable to login to icloud on MacBook Air.
Tried steps mentioned about Keychain access but didn't help. How do I login to icloud on the machine.
iPhone 12, iOS 14