Password lost emails not sent

When requesting a password reset, it states that it is sent, but it never arrived.

From mail.log:
Oct 24 21:07:39 server1 postfix/submission/smtpd[29174]: connect from server1.example.com[IP-ADRESS]
Oct 24 21:07:39 server1 postfix/submission/smtpd[29174]: warning: non-SMTP command from server1.example.com[IP-ADRESS]: Subject: =?UTF-8?B?Q29uZmlybSBJU1BDb25maWcgMyBDb250cm9sIHBhbmVsIHBhc3N3b3JkIHJlc2V0?=
Oct 24 21:07:39 server1 postfix/submission/smtpd[29174]: disconnect from server1.example.com[IP-ADRESS] helo=1 starttls=1 auth=0/1 mail=0/1 rcpt=0/1 data=0/1 unknown=0/3 commands=2/9