Preferences says "this account already exists" when trying to change password in Mail.
Mail keeps asking me for the password for my email account. When I type it in, it says "This account already exists." No problem, I think. I have had this email for over 20 years so, yes, it does exist. I think there must be a problem with my email/internet company, so I changed the password with them thinking I could just change the password on Preferences since it is a new password. No deal! I have tried different things, none of which seem to work. Suggestions??
iMac 21.5", macOS 10.15