DIRG820108MYNZMD05

You either don't have SMTP configured or SMTP is failing and it's attempting to send from PHPMail as a backup however that is also failing. It's failing as you likely don't have your PHPMail configured (not that many people do these days). Moral of the story is to setup SMTP and you should be good.

Reference:

• https://docs.osticket.com/en/latest/Getting%20Started/Email%20Settings.html

Cheers.