Netsuite emails always suspended

All emails received from Netsuite are going directly to our Suspended Tickets folder and need to be manually recovered. We have a major customer that sends all emails through Netsuite so multiple times per day we need to scrub that folder for their legitimate emails which include purchase orders, cancellations and other time sensitive communications and replies.

This has to have been asked before, but I cannot find the thread. Would appreciate any suggestions for troubleshooting and/or any settings that we're missing. Yes, they are whitelisted...