Apple Mail

I am using MacOS Majove and have for years. I was trying to clear up a small issue on the Apple Mail not syncing with the trash on Exchange. In doing that a tech with Godaddy told me to delete the mail and then re-add it. Now I cannot get Exchange to complete the adding a new account. Does anyone know how to add the account back with this OS system. I don't want to upgrade to OS Big Sur as when I attempted that it goofs up my microsoft and other software.