[BruceH]

I had the same problem when I sold my 2014 Leaf; I contacted Nissan customer services through the website and they manually removed it for me. Apparently it was down to my account having been created many years ago, it was never properly migrated to the newer web-based owner portal, so impossible for me to log in to it to remove my car. They fixed it within 24 hours so hopefully they will resolve for you as well.