DNS Server Failure

Yeah that one does pretty much the same as what I suggested.

Check out the excellent docs and in particular the examples for some popular routers in the "Router setup" section:

EDIT: Oh and use nslookup allot to diagnose on your clients (Windows, MacOS or Linux) before fiddling with router settings!

nslookup <DOMAIN_NAME> <DNS_SERVER_IP>

Eg:

C:\>nslookup pi.hole 10.0.0.2
Server:  ph6a.home.dehakkelaar.nl
Address:  10.0.0.2

Name:    pi.hole.home.dehakkelaar.nl
Addresses:  fe80:XXXX
          10.0.0.2

And after router changes:

C:\>nslookup pi.hole
Server:  ph6a.home.dehakkelaar.nl
Address:  10.0.0.2

Name:    pi.hole.home.dehakkelaar.nl
Addresses:  fe80:XXXX
          10.0.0.2

My victory was short lived.

I set up a bridge between my ethernet connection and USB connection to send internet to my TV with a USB to ethernet-adapter after setting up a USBgadget. Now I have successfully allowed my TV to connect to the internet but broke Pi-hole again.

https://tricorder.pi-hole.net/x9UNCwuH/

Any advice?