Email sent 'via registrar-servers.com'

[andrewvinci]

We've been using M365 email, and have noticed that, particularly on gmail, it throws a 'via registrar-servers.com' flag at the end. While it all works fine, it would be good to get it sorted. Is there some DNS record I'm missing or some other way to address this?

[#2]

@andrewvinci Hey!
Could you please submit a email header, then it will be a little easier to help you

[#3]

@Pontus Själander Sorry for the late reply - the usual more urgent issues come up!

I have attached the full header. registrar-servers.com does appear - but honestly I have no idea why!

edit: apparently I can't attach .txt files. go figure. so now it's a mangled word doc haha.

[#4]

@andrewvinci 
If possible, please send me a Personal Message with the complete addresses and domains, so we can check all records related to the mailflow