else statement not working in active admin

Else statement not working in active admin. Any help will be appreciate it

  show do
    attributes_table do
      row :id
      row :user
      if :address_id.empty?
        row :user_id do |n|
          n.user.address
        end
        row "Phone",:user_id do |n|
          n.user.phone
        end
      else 
        row :address_id do |n|
          n.addresses.last&.name
        end
        row "Phone",:address_id do |n|
          n.addresses.last&.phone
        end
      end
      
      
    end
  end

the result of my codes is when the address_id is empty the result will be empty not this row :address_id do |n| n.addresses.last&.name end row "Phone",:address_id do |n| n.addresses.last&.phone end