Bravo List - tsue 2.2 email issues

how i can fix this error

postfix/smtp [10894]
C77243C0671: to=, relay=gmail-smtp-in.l.google.com[122.51.173.47]:25, delay=1.2, delays=0.53/0.02/0.37/0.27, dsn=5.7.1, status=bounced (host gmail-smtp-in.l.google.com[122.51.173.47] said: 550-5.7.1 This message is not RFC 5322 compliant. There are multiple Date 550-5.7.1 headers. To reduce the amount of spam sent to Gmail, this message has 550-5.7.1 been blocked. For more information, go to 550-5.7.1 https://support.google.com/mail/?p=R...geNonCompliant and review 550 5.7.1 RFC 5322 specifications. ea2-20020a0560000ec200b0034640aeb886si2908606wrb.630 - gsmtp (in reply to end of DATA command))