ActionMailer acting different on production server - ruby-on-rails

Question

I have a action mailer method as something like this:
def mail
#receiver = User.where(status: 2).pluck(:email)
mail(bcc:#receiver, to: "username#gmail.com")
end
application.yml looks like this:
SMTP_ADDRESS: 'smtp.gmail.com'
SMTP_PORT: 587
SMTP_HOST: 'localhost:3000'
SMTP_DOMAIN: 'localhost:3000'
SMTP_USERNAME: 'user#gmail.com'
SMTP_PASSWORD: 'xxxxx'
SUPER_ADMIN_EMAIL: 'super_admin#mailinator.com'
developmet.rb looks like this:
config.action_mailer.asset_host = ENV["SMTP_HOST"]
# config.action_mailer.delivery_method = :letter_opener
config.action_mailer.raise_delivery_errors = false
config.action_mailer.delivery_method = :smtp
config.action_mailer.smtp_settings = {
#Enter the smtp provider here ex: smtp.mandrillapp.com
address: ENV["SMTP_ADDRESS"],
port: ENV['SMTP_PORT'].to_i,
#Enter the smtp domain here ex: vendaxo.com
domain: ENV["SMTP_DOMAIN"],
#Enter the user name for smtp provider here
user_name: ENV["SMTP_USERNAME"],
#Enter the password for smtp provider here
password: ENV["SMTP_PASSWORD"],
authentication: 'plain',
enable_starttls_auto: true
Where receivers are kept in BCC but "username#gmail.com" will be able to see the BCCd receivers. This is working fine when I send the mails from my local host. When receivers are sent emails, all of them are in BCC and one 'username#gmail.com' is able to see all the receivers.
But when I do the same thing on production server with similar application.yml configuration changing the host and port the username#gmail.com is NOT GETTING the emails of BCCd receivers.

Answer 1

I think if you are running your production server on AWS EC2 (may be other providers too), every time you do some changes to your application.yml or any other shared file, you need to restart the app server in order to apply the changed configurations . In my case I had to restart the PUMA, and the one default email started to get BCCd email ids.