The mailman is a Nazotchi, and the V3 doesn't know the V4 characters because I figured there not really connecting, there just reading the other tamagotchis system 2 know what character/name your tama has. Then the other tama "comes over" to the friend's house. So since the V4 has new characrers, the V3 doesnt know them all, so whatever it doesnt know it puts a Nazotchi for it.