If you're referring to the step I think you are, it's not neighbors you need to visit...it is Community Members--that is, members in the community who are NOT our neighbors (I made the same mistake initially). To know if you've completed the goal, you can check the goal itself, or you can tap on the Festive Workshop to see if you've gotten the Present from Jed (tap on the recipe for the White Elephant Gift), or on a Festive Tree to see if you've received the White Elephant Gift.