In my DNS Server Event Log, I have received an incredibly large amount of entries with Event ID 5504. The text within the event entry is as follows: "The DNS server encountered an invalid domain name in a packet from 18.104.22.168. The packet is rejected." Why am I receiving so many packets from this specific IP address? Should I be concerned? Should I try and block this IP address from my network? Any suggestions would be greatly appreciated. Thank you.