If you have tried to message someone you didn’t know, recently, you may have noticed Facebook has added a Pay-to-Message feature. In most cases you are prompted to pay $1, but the fee ranges from $1 to $15 depending on that person’s popularity. If you choose not to pay to message the person, Facebook will give you an option to send a message to their “other box.
Right now, users are not notified of “other” messages and its location is not very prevalent, so Facebook depends on the urgency to see the message. Users are not trained to look for other messages, they usually look directly at new messages. But alas, you do not have to pay the fee!
Users can find “other” messages to the right of the Inbox indicator. If there are messages, they will be a grayed number. After messaging them, try searching their Facebook About page for other forms of contact. Sometimes you can find phone numbers or other networks listed. Facebook changed most users primary email address to a Facebook email address. Those messages also go to the “other” messages. area. I also recommend searching for Twitter or Google+ accounts, as an alternate means of free communication.