Please follow the below template, it will help us to help you!
Expected Behaviour:
Installed PiHole today on a raspberry pi 2 B+ new raspian buster lite install connected to vodafone Vox 2.5 router by ethernet. Expected it to work.
Actual Behaviour:
When I replace the vodafone router default DNS server with the IP of my pihole I lose internet connection for connected clients with DNS failure. I have enabled the 'listen to all' option in admin console and have tried both with and without DHCP server running on pihole. Same result with both.
Debug Token:
Token before disabling DNS 8.8.4.4 - https://tricorder.pi-hole.net/h0ykhtubuz
Token after making sure PiHole is only DNS address - https://tricorder.pi-hole.net/ku9ul5wvn4