CF7 mail not send or spam

Hello,

I have 3 forms on my website build with CF7 :

• Contact
• Booking (via the show post – takes directly the infos of the show)
• Booking (via the reservation form – dropdown list of shows)

-> They are all sent on [email protected]

The WP mail SMTP is well configured with my host settings.
CF7 “To”, “From” and Additional header fields are set with [email protected] or [email protected] (who considerably exist on my host).

Several issues:

• The form doesn’t send itself -> error message = spam
• The form sends but the mail is not received by the recipient. Only the version for the info address.
• The form and the mails are sent but fall directly into the spam box.

I have done a lot of sending tests from two of my personal addresses and also via mail-tester.com

Mail-tester initially gave me a good result by specifying that a DMARC key was missing on my server and that the DNS was not up to date yet.
I added the DMARC key. I imagine that updating my DNS data will be done on its own.
All other tests proved to be less good. One of them even specified that I was black listed on SORBS via my IP.
About the images, no remark. So, the fact that mails fall into junk box is not related to this.

Anybody help please ?

Have a nice day