Redmine

Hello,
I can't make my notifications work.
Here is what I wrote in configuration.yml
delivery_method: :smtp
smtp_settings:
enable_starttls_auto: true
address: smtp.gmail.com
port: 587
domain: smtp.gmail.com
authentication: :login
user_name: antoine.tran at bcs-development.com
password: xxxxxxxx
I'm using gmail.
I've restarted redmine but it still doesn't work.
In my settings I wrote "Default notification option: for any event on all my projects"

Any help would be highly appreciated.
Thanks.