You should check to see if the messages that are being sent contain any links that would be considered questionable/spammy. You can also try taking the content of one of the messages and checking it’s spam assassin score ( https://spamcheck.postmarkapp.com ). Source: over 2 years ago

Build a clean email that passes a spam check with flying colors (https://spamcheck.postmarkapp.com/) then use a warmup service like lemwarm, inboxally or neverspam as mentioned in the other comments. Source: almost 3 years ago

The issue sounds more email centric. You're likely hitting the Apache SpamAssassin limit on the remote email servers. Use https://spamcheck.postmarkapp.com/ to check the score of emails you've had declared spam, and follow recommendations to improve. Source: almost 3 years ago

A tool is Inbox When Ready that lets you control your email interruptions. Source: almost 2 years ago

So, I downloaded InboxWhenReady to block my inbox except for two one-hour windows throughout the day. I use a form of Inbox Zero where I triage each message and decide whether to:. - Source: dev.to / over 2 years ago

> Fixing the hive-mind is going to be a billion dollar industry Cal Newport was one of the inspirations for https://inboxwhenready.org. At this point, people have paid me over $100K to make it harder for them to read their email. - Source: Hacker News / almost 3 years ago