Unable to send mail from Webmin

Hello,

I have a fresh install of Webmin, where i created a Backup Schedule of MySql Databases and added a mail confirmation for every successful backups. When i do a manual backup or automatic backup, even after a successful backup, i don't receive any mail.

I checked maillog, i don't see the mail being sent. Also, it is not in the queue. I tried with Sendmail being the default and also with Postfix after disabling Sendmail.

Note: Local E-Mail alerts like SSH login failure, SU alerts work fine, i can read them using "Read User Mail" --> "Username"

Thanks.