Lots of DNS Server events 5504 on AD DNS server from Cloudflare etc

Hi! I'm getting about 18 events with id 5504 while trying to resolve some DNS names, like fullfiles.xyz.

The DNS server is configured to use provider DNS and root hints.

I can suppress these messages by disabling root hints or by disabling EDNS0 with dnscmd /config /enablednsprobes 0.

I tried to use packet capture on the DC and on the router, and analyzed the results with AI, which answered:

"You receive malformed patterns on the WAN interface."

Can anybody explain the cause of this problem? Any ideas to fix it?

Thanks!