So I ran the commands below after setting up my router to turn off DHCP and on, on the pi, and set my DNS to point to the pi.
My phone took the new settings and I wasn’t able to upload the images until I set my dns to 8.8.8.8 manually on my phone and removed the ‘pie’ from my search domains.
I’m not getting internet on the Pi either with DHCP and DNS active on the Pi only.
I restarted the Pi and my laptop and the laptop is getting DNS and DHCP from the Pi. I tried your nslookups for flurry.com again and got the same results.
Setting my router back to handle DHCP and my primary DNS to point to the Pi, and the secondary to point to 192.168.1.2 (which I would think would then go to the primary), and trying to go to flurry.com, it allows me to go to it.
If I change my dns on my phone manually to point to the Pi, and go to flurry.com it blocks it, but if I try any other website, they don’t load, but the request shows up as forwarded in the Pi interface.
You probably have your Pi-hole device set up to get the ip via dhcp from your router and when you rebooted or, it got a new ip and resolution started failing.
You need to set up your raspberry with a static lan ip. That will provide consistency.