some results in a PM, but a think (hope) I found a reason why...
remember (previous discussions) , I'm on windows 10 20H2, with IPv4 (fixed address) and IPv6 (temporary IPv6 address, default out of the MS box). The IPv6 address changes every day, or after a reboot/restart. The fact the IPv6 address changes isn't really a problem, the fact that the windows 10 system has both IPv4 and IPv6 (GUA) appears to be a problem (I think).
Look at this very short list of queries, registered in the pihole.log today.
cat /var/log/pihole/pihole.log | grep www.whotracks.me
Apr 8 17:58:22 dnsmasq[18854]: 14786 192.168.2.228/60196 query[A] www.whotracks.me from 192.168.2.228
Apr 8 17:58:22 dnsmasq[18854]: 14786 192.168.2.228/60196 forwarded www.whotracks.me to fdaa:bbcc:ddee:2::5552
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 query[AAAA] www.whotracks.me from 192.168.2.228
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 forwarded www.whotracks.me to fdaa:bbcc:ddee:2::5552
Apr 8 17:58:22 dnsmasq[18854]: 14788 2a02:1810:4d02:6903:7dff:b06a:aed4:9194/59656 query[AAAA] www.whotracks.me from 2a02:1810:4d02:6903:7dff:b06a:aed4:9194
Apr 8 17:58:22 dnsmasq[18854]: 14789 2a02:1810:4d02:6903:7dff:b06a:aed4:9194/60196 query[A] www.whotracks.me from 2a02:1810:4d02:6903:7dff:b06a:aed4:9194
Apr 8 17:58:22 dnsmasq[18854]: 14786 192.168.2.228/60196 reply www.whotracks.me is 13.226.159.6
Apr 8 17:58:22 dnsmasq[18854]: 14786 192.168.2.228/60196 reply www.whotracks.me is 13.226.159.11
Apr 8 17:58:22 dnsmasq[18854]: 14786 192.168.2.228/60196 reply www.whotracks.me is 13.226.159.31
Apr 8 17:58:22 dnsmasq[18854]: 14786 192.168.2.228/60196 reply www.whotracks.me is 13.226.159.75
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 reply www.whotracks.me is 2600:9000:21d7:200:10:8b76:f140:93a1
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 reply www.whotracks.me is 2600:9000:21d7:9800:10:8b76:f140:93a1
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 reply www.whotracks.me is 2600:9000:21d7:2c00:10:8b76:f140:93a1
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 reply www.whotracks.me is 2600:9000:21d7:6000:10:8b76:f140:93a1
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 reply www.whotracks.me is 2600:9000:21d7:3600:10:8b76:f140:93a1
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 reply www.whotracks.me is 2600:9000:21d7:8c00:10:8b76:f140:93a1
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 reply www.whotracks.me is 2600:9000:21d7:a600:10:8b76:f140:93a1
Apr 8 17:58:22 dnsmasq[18854]: 14787 192.168.2.228/59656 reply www.whotracks.me is 2600:9000:21d7:b800:10:8b76:f140:93a1
The system does a A and AAAA query (first four (4) lines), using the IPv4 address, these are forwarded.
Than, the next two (2) lines, there is an A and AAAA, using the IPv6 address, apparently NOT forwarded, but using the same source port as the IPv4 queries did
The database entries:
If I read everything correct in the dnsmasq discussion group, the source port match causes dnsmasq to mark them as retries.
If my analysis is correct (NOT sure) this might be a windows problem, I have NO idea how to fix this...
I hope another windows 10 user reads this, perform the same tests, and hopefully confirm my diagnose...