Why doesn't mogolab save objects (golang, driver "gopkg.in/mgo.v2", )?

Question

MongoDB

only ID is added to Mongolian.
I can't figure out what could be the problem.
"_id": {
"$oid": "56bdfce2e8d67ac70dfe137e"
}

col := session.DB(database).C(collection)
session.SetMode(mgo.Monotonic, true)
session.SetMode(mgo.Monotonic, true)
count, err2 := col.Count()
if err2 != nil {
panic(err2)
}
fmt.Println(fmt.Sprintf("Messages count: %d", count))
err = session.DB(database).Login(username, password);
if err != nil {
panic(err)
}
err = col.Insert(&Person{name:"TestName", Pone:"[phone]"})