Laravel: Failed to authenticate on SMTP server with username "xxx@xxxxx.com.au" using 2 possible authenticators

I am trying to send emails from my application using SMTP server. My mail settings in env file are as below -

MAIL_DRIVER=smtp 
MAIL_HOST=mail.xxxxx.com.au 
MAIL_PORT=465 
MAIL_USERNAME=xxx@xxxxx.com.au 
MAIL_PASSWORD=mySymbolicPassword 
MAIL_ENCRYPTION=ssl

When I use the gmail mail account settings, it works perfectly fine over mail port 587 and encryption to be TLS. When I change this to another mail server it fails with an error -

"Failed to authenticate on SMTP server with username "xxx@xxxxx.com.au" using 2 possible authenticators"

Is there anything I am missing here?

via Chebli Mohamed