It seems I am completely inept when it comes to using the postal system.
This is the second attempt I've made at sending a friend a package, and after a three week jaunt has been returned.
Previously was a transcription error on my part.
This time, some kind soul overwrote part of the zip code. Possibly another person wrote "Unknown" on the box, it got stamped "ATTEMPTED NOT KNOWN" and returned to me.
Time to go find another box. Blech.