Your network isn't using Pi-hole as DNS server.
It's using the device at 2600:<redacted>:6500::1, likely your router, thus bypassing Pi-hole.
This may be the case because Pi-hole isn't aware of its correct IPv6 address because your IPv6 prefix has changed (likely by your ISP, from 2600:<redacted>:5800 at the time of Pi-hole's installation to 2600:<redacted>:6500 now):
*** [ DIAGNOSING ]: Setup variables
IPV6_ADDRESS=2600:<redacted>:5800:<redacted>:f3d1
*** [ DIAGNOSING ]: Name resolution (IPv6) using a random blocked domain and a known ad-serving domain
[✗] Failed to resolve sm3na.com via Pi-hole (2600:<redacted>:5800:<redacted>:f3d1)
You could consider to Use IPv6 ULA addresses for Pi-hole.