Email marketing issue

You have to warm up your email list and also some salesy email automatically goes to spam. Generally any email software that you use, you should routine the email by sending it to small numbers and gradually increase.

• Don’t use long paragraphs.
• Don’t abuse the subject line - include only what’s needed.
• Don’t add unnecessary attachments.

You need to know the technical side and its influence on email deliverability:

1. Avoid using dynamic IPs
2. Check the IP reputation regularly
3. Verify all email lists
4. Follow your email campaign open and spam complaint rates
5. Know the bounce rate
6. Warm-up new email accounts before sending large campaigns
7. Create a separate email account for outbound marketing
8. Send personalized emails
9. Track links right
   More useful information in the article https://snov.io/blog/how-to-avoid-spam-filters/
   I hope it will help you avoid getting into spam.

Great question. I'm a partner with Constant Contact and this has been brought up a lot in the last couple years - seems to be getting worse over time. I'm going to check out @andwemet 's suggestion, but I'm not sure there's much you can do.