Some of your incoming emails are getting tagged as spam by spamassassin.
In the email headers you will see the checks spamassassin performed to tag the emails. By default a score of 5 or above will mark the email as spam.
X-Spam-Flag: YES X-Spam-Score: 5.749 X-Spam-Level: ***** X-Spam-Status: Yes, score=5.749 tagged_above=-1000 required=5 tests=[HTML_MESSAGE=0.001, LOCALPART_IN_SUBJECT=0.73, RDNS_NONE=1.274, TO_NAME_SUBJ_NO_RDNS=2.999, URIBL_BLOCKED=0.001, URIBL_SBL=0.644, URIBL_SBL_A=0.1] autolearn=no autolearn_force=no
The most scoring tests are TO_NAME_SUBJ_NO_RDNS and RDNS_NONE which is sort of double check as both tests check for DNS resolution.
Add your sender’s email address to the whitelist in