Pihole seems to upstream your requests although there is a local entry for that domain in your settings. Maybe it has something to do with using IPv6? Maybe your device prefers the cloudflare IPv6 over your local IPv4 address.

Or Maybe your device queries your pihole as well as your Router to get the IP. Check your current dns server on your device: ipconfig /all (Windows)

I have the (more or less) same setup. Your DNS entries on your pihole instance should point to the local ip of your server (192.168.x.x).

If thats the case check the dns settings of your router. Under DHCP settings there should be a input field for your dns server. This has to be the local IP of your pihole.

One thing you could do to start diagnosing the Problem is running this command: nslookup servicename.yourdomain.tld. This should return your local IP and not a public one.

How do you determine that the requests are leaving your Network?