I just upgrades to a pi zero 2 with the new 64bit OS and I started having this issue on one machine:
It was manually configured to DNS to the Pi-hole address. I switched to 'automatically' and it ended throwing errors.
The address was correct but something thought it was more than one hop.
There is a thread on this that gives a command line to log the device IP address but I do not remember what it was.
Their answer is here on that page, listed as:
Ignoring query from non-local network
dnsmasq can be configured to only accept queries from at-most-one-hop-away addresses using the option local-service . Other queries are discarded in this case.
This is ment to be a safe default to keep otherwise unconfigured installations safe. Note that local-service is ignored if any access-control config is in place ( interface , except-interface , listen-address or auth-server ).
But trying to figure out which client is having trouble needs a command line not in the answer provided.
I found it by looking around at other threads. Something about changing FTL from main to... ...something... and then, after finding the culprit, going back to the main.
I'd tell you what it was but I moved the zero 2 to another monitor and it is being flaky with a blank screen.
Edit
I found the command that will log the device (or revert), but I do not know which it is nor have both:
pihole checkout ftl new/non_local_details
That will either log the device next time it tosses an error or revert to normal
Wait until a mod clears this up.
It will SCREAM it is dangerous to use, so someone will help clarify now that I have put it in the wild without a way to fix it.
2nd edit
I found the thread for you: