Hello Amol

Issue with email notifications could be caused by several reasons:

1. Your hosting provider is blocking all 3rd party settings, and only allowing their SMTP (or other) settings. 

2. Your website has PHP version less than 7 

3. The credentials are not correct 

4. There's something else blocking the notifications from being sent.

Please check these points, and let me know if you were able to resolve the issue. If you're not able to resolve the issue, please provide me a temporary WP-admin login for your site where this happens, so we could log in and take a look ‘from the inside’ as that’s the most efficient way to see and resolve the issue. We do not interfere with any data or anything else except for the plugin (in case that’s a production version of the site), and of course we do not provide login data to third party. You can write credentials here because this ticket is private and nobody can see it except us.

Hello Amol

There's nothing within Amelia that can prevent this from happening.

You can take a look at this thread, and hopefully it will help you out resolve this issue.