Ghost login/passwords in keychain.

See the article How to find saved passwords and passkeys on your Mac - Apple Support

If web sites are not important you can right click over them ( in the location safari > preferences ) > password section ( enter admin password ) to open , right click over them and click on delete .

See another article Remove a passkey or password from your Mac and iCloud Keychain - Apple Support (

Note : when you delete the password , the new password has to be updated and click on save , the website and its password will be saved , in fact what you are doing is just deleting the password , and not adding a new password and clicking on save , that's the reason the different websites and their password is again saved and not getting deleted .

Is your Mac refurbished ? then erase the hard drive and reinstall Mac OS What to do before you sell, give away, or trade in your Mac - Apple Support if there are no pops up appearing you don't need them to delete .

Are you seeing the items in user library > in keychain folders .

Click on finder > Go > hold option key > click on library > keychains the password are saved in first folder .

You must not delete old login passwords , let them be saved in keychain access , in case if keychain access has no issues if you try to delete them the keychain might be corrupted .

Then where are you looking those passwords , post a screen shot ( hide any mail address / user name ) .