i followed your guide from this thread Verzweiflung pur - Lange Verzögerungen & Ladezeiten oder gar keine Funktionen - #13 by Bucking_Horn and still i see in windows that it fetches both ipv6 addresses for the dns. The first entry is the fritz.box the second one my pihole
i managed from your guide already, that even after reboot the ipv6 stays the same and starts with fd00 - i added the ipv5 to /etc/dhcpcd.conf and /etc/pihole/setupVars.conf and also to /etc/pihole/local.list
also in the fritzbox dns settings i added the new static ipv6 like mentioned in your guide. i still get this output on my windows mashine with nslookup pi.hole
Server: fritz.box
Address: fd00::9a9b:cbff:fe61:XXXX
*** pi.hole wurde von fritz.box nicht gefunden: Non-existent domain.