I have a local Adguard home sever, which is used as DNS and DHCP Server. This is completely working fine on my Computers. I was wondering why my phone is still showing ads which were blocked on my PC.

Then I found out that my mobile device is not using my local DNS. I am using a public tld in my home to have valid let's encrypt certs also on my private services. But this is not working on my Android. I found out that my phone is using hard coded DoH Servers. I found people with the same problem online, they are blocking DoH and routing all Port 53 traffic to the local DNS. I did the same. But the only thing I get as result is a timeout in the mobile Webbrowser.

How is it possible to use my local DNS server with public tld on mobiles? Any help is appreciated 👍