Once address was added contact names do not print. No errors.

require './phone_number'
require './address'

class Contact
  attr_writer :first_name, :middle_name, :last_name
  attr_reader :phone_numbers, :addresses

  def initialize
    @phone_numbers = []
    @addresses = []
  end

  def add_phone_number(kind, number)
    phone_number = PhoneNumber.new
    phone_number.kind = kind
    phone_number.number = number
    phone_numbers.push(phone_number)
  end

  def add_address(kind, street_1, street_2, city, state, postal_code)
    address = Address.new
    address.kind = kind
    address.street_1 = street_1
    address.street_2 = street_2
    address.city = city
    address.state = state
    address.postal_code = postal_code
    addresses.push(address)
  end

  def first_name
    @first_name
  end

  def middle_name
    @middle_name
  end

  def last_name
    @last_name
  end

  def first_last
    first_name + " " + last_name
  end

  def last_first
    last_first = last_name
    last_first += ", "
    last_first += first_name
    if !@middle_name.nil?
      last_first += " "
      last_first += middle_name.slice(0, 1)
      last_first += "."
    end
    last_first
  end

  def full_name
    full_name = first_name
    if !@middle_name.nil?
      full_name += " "
      full_name += middle_name
    end
    full_name += ' '
    full_name += last_name
    full_name
  end

  def to_s(format = 'full_name')
    case format
    when 'full_name'
      full_name
    when 'last_first'
      last_first
    when 'first'
      first_name
    when 'last'
      last_name
    else
      first_last
    end
  end

  def print_phone_numbers
    puts "Phone Numbers"
    phone_numbers.each { |phone_number| puts phone_number }
  end

  def print_addresses
    puts "Addresses"
    addresses.each { |address| puts address.to_s('short') }
  end
end

jason = Contact.new
jason.first_name = "Jason"
jason.last_name = "Seifer"
jason.add_phone_number("Home", "123-456-7890")
jason.add_phone_number("Work", "456-789-0123")
jason.add_address("Home", "123 Main St.", "", "Portland", "OR", "12345")

puts jason.to_s('full_name')
jason.print_phone_numbers
jason.print_addresses

class Address
    attr_accessor :kind, :street_1, :street_2, :city, :state, :postal_code

    def to_s(format = 'short')
        address = ''
        case format
        when 'long'
            address += street_1 + "\n"
            address += street_2 + "\n" if !street_2.nil?
            address += "#{city}, #{state} #{postal_code}"
        when 'short'
            address += "#{kind}: "
            address += street_1
            if street_2
                address += " " + street_2
            end
            address += ", #{city}, #{state} #{postal_code}"
        end
        address
    end
end

home = Address.new
home.kind = "Home"
home.street_1 = "123 Main St."
home.city = "Portland"
home.state = "OR"
home.postal_code = "12345"

puts home.to_s('short')
puts "\n"
puts home.to_s('long')

class PhoneNumber
    attr_accessor :kind, :number

    def to_s
        "#{kind}: #{number}"
    end
end