I sent out my invitations 3 weeks ago and a handful of people never received them ! Even some people in our same zip code ! We haven't gotten any back . I've called the post office and they said they can't do anything since it wasn't certified and didn't have a tracking number . I didn't think I needed that for an invitation !!! Now I feel like $200 has been wasted . Has this happened to anyone else ? What did you do !?