Email Notification Issue

[CBuilder]

Hello

I have set email notification settings like below, but I am not receiving any emails

$g_enable_email_notification = ON;
$g_phpMailer_method = PHPMAILER_METHOD_SMTP;
$g_smtp_host = 'smtp.gmail.com';
$g_smtp_connection_mode = 'tls';
$g_smtp_port = 587;
$g_smtp_username = 'alert@domain.com';
$g_smtp_password = 'pass';


The Mantis log shows the following notes

2015-11-30 10:59 CET mail_recipient Issue = #90, add Reporter = @U3
2015-11-30 10:59 CET mail_recipient Issue = #90, add Handler = @U10
2015-11-30 10:59 CET mail_recipient Issue = #90, add Monitor = @U3
2015-11-30 10:59 CET mail_recipient Issue = #90, add Project User = @U10
2015-11-30 10:59 CET mail_recipient Issue = #90, add Project User = @U3
2015-11-30 10:59 CET mail_recipient Issue = #90, add Project User = @U12
2015-11-30 10:59 CET mail_recipient Issue = #90, drop @U3 (own)
2015-11-30 10:59 CET mail_recipient Issue = #90, drop @U10 (pref email_on_status off)
2015-11-30 10:59 CET mail_recipient Issue = #90, drop @U12 (pref email_on_status off)

Please help me

Thanks