I have Netlify DNS set up for my domain www.kometa.xyz that I also use to send emails and serve another website (hosted elsewhere). It seems I have a reverse DNS problem that could be fixed via a PTR record: https://www.dropbox.com/s/sfbznpn7iebt3jc/Screenshot%202020-01-27%20at%2012.42.45.png?dl=0. Can I insert such record or is there any alternative solution to fix this issue? Thank you!
Whatever your problem is, no PTR record that Netlify can affect will solve it. Those are set by the people who control the IP of your services, and would not be something we’d set for you.
I’d suggest checking in with the tech support at your mail provider for some help as that solution does not sound correct to me.