how to permanently delete a name from e-mail dropdown "to" menu on Mac e-mail that appears but is not in "contacts"
Every time I type "ah..." on the "To" dropdown e-mail menu, an unknown address comes up that does not appear in my contacts. I've tried to permanently delete it but keeps appearing. I also cannot find it anywhere on the computer when I search for it. How can I permanently delete it.
MacBook Pro 15″, macOS 10.14
