Hey im doing a test on my VPS systems i installed debian with exim 4.69

and when i run the metasploit this is what happens

[-] Exploit exception: RCPT: 550-dsl181157.$$$$$$$$$$.net (zbwQXWNO.com) [MY IP ADDRESS ] is currently not
550-permitted to relay through this server. Perhaps you have not logged into
550-the pop/imap server in the last 30 minutes or do not have SMTP
550 Authentication turned on in your email client.[*] Exploit completed, but no session was created.
Any idea? how to fix this