@David-TP That's very helpful and explains the situation well. Thanks for sharing that link.

@David-TP Thanks for your reply. My ISP is Comcast/xFinity.

Yesterday, oddly and for the first time, spamhaus states that I am on the "Spamhaus Blocklist": "73.113.200.244 has 1 listing" On the Deco app, my IPv4 Connection is Dynamic and shows 73.113.200.244...