Change the Auto-Complete options

The Auto-Complete feature stores any entries that you type in a PDF form field, and then suggests or even automatically enters responses that match your typing in other form fields. The suggestions appear in a pop-up menu, from which you can select a match. The Auto-Complete feature is off by default, so you must enable it in the forms preferences if you want to use it.

If you want to remove an entry from the Auto-Complete memory