Email gets sent but I never receive it

We have also started to receive this on every domain we are using the Contact Form 7 on, we are trying to work out why. We know the server is not blacklisted as that is come up clean so we are also looking into is it a setting, do we need to change something on the DNS of server maybe.

Support says ” Showing the green border message means that the PHP function for sending the mail has certainly completed successfully. So if you can’t receive the mail, it’s highly possible that the mail has been kidnapped or killed after that. If you can check the log of your mail server, it could give you some clues. Spam filter often causes this kind of problem.”

I am wondering here if it is a SPF issue maybe on the DNS?

I might have found the issue. I think the issue is PHP Mail in the database from the hosting server. https://wpmailsmtp.com/contact-form-7-not-sending-emails/ if that is not in place and many are not anymore then this will create the issue. I know the server company we use no longer support PHP emails and we move email to Microsoft, so that would explain it. The problem now stems to whether they will add it to the server or whether they will not and in that case i think I have to move all the websites we have.

What other plugins and theme do you use on the site?

We have managed to establish that the issue is most likely with our server hosting company. As we have multiple websites on our server using the form so they are now running tests to see if they can get the form to send emails. Hopefully this will solve it and if it does will post on here so others can be aware.