Check that your ISP doesn't block inbound connections on port 80. In the US, there is a growing trend of residential providers blocking those and other common service-hosting connections upstream unless you change to a "business" account. You may also be behind a CGNAT ISP, unless you have successfully gotten external port-forwards working in the past. The second is much less likely, and I have only seen it from the new, smaller fiber startups popping up who were not around when the Class A Subnets were allocated...