Emails keep getting in spam or not getting delivered

I try setting up smtp for my forums. I googled it and tried all different solutions.

Services i tried:
- mailgun
- elasticemail
- gmail
- host email

I added all records which were needed on host and on cloudflare. The only thing works is sending with host email but they all go to spam i tried the class_mailhandler change technique did not work. And it feels like i have no idea anymore what to do!

This is the error i get with all other mail services other then host email.


What could i do to solve it?