Hi i have problems with sending emails from my droplets. I am usim exim. I tested for example by typing

mailx ***@gmail.com -s"TEST"
TEST
.
but I am receiving this error:

2017-12-16 18:19:17 1eQH3M-00031M-Ud ** ***@gmail.com R=lookuphost T=remote_smtp H=gmail-
smtp-in.l.google.com [209.85.232.27] X=TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128 CV=yes: SMTP error from remote mail server after end of data: 550-5.7.1 This message does not have authentication information or fails to pass\n550-5.7.1 authentication checks. To best protect our users from spam, the\n550-5.7.1 message has been blocked. Please visit\n550-5.7.1 https://support.google.com/mail/answer/81126#authentication for more\n550 5.7.1 information. p14si3542435qki.429 - gsmtp

If I try protonmail:

2:ECDHE-RSA-AES256-GCM-SHA384:256 CV=yes: SMTP error from remote mail server after RCPT TO:<****@protonmail.com>: 504 5.5.2 root@localhost: Sender address rejected: need fully-qualified address

Please help :)