All ports scan as closed

I have a comcast modem with DHCP public IP address of that is being passed to my Unifi USG using No-IP DDNS.  The Comcast modem is set to basic bridge mode.  The firewall and WiFi radios are completely shut off.  About two days ago my access stopped to my camera web server via port 81 that is defined by a port forward rule in my Unifi firewall.  This setup has been working perfectly for months.  I know there were absolutely no changes to any network component or computer of any kind because I am the only one who works on the IT stuff .   When I scan my public IP via yougetsignal.com and NMap I get that all common ports are blocked including port 80 & 443.  In fact NMap doesn't even find a connection because the IP doesn't respond to pings.  How is this possible? Did Comcast change something recently so that my IPv4 address in the 68.57.XXX.XX range is no longer publicly routable?  I'm stumped and first level Comcast support was so bad I'm not calling back!!