A long time ago I used spectrum and their modem/router combo with 200/10mbps and port forwarded fine.
Then, I moved to a bigger city, got google fiber. I tried working with 2 different support teams at google to figure out why its not working, no one could figure it out. The google wifi router team kept saying its the ISP (google fiber) and the ISP kept saying it was the router. Moved again a year later, got spectrum so I could port forward, only other option is ATT... Some googling revealed that the modem/router combo unit aint the play for port forwarding, and also no $5/m charge so hey, i'll just get the free modem. Turns out I still cant port forward, for unknown reasons. Firewall is still set correctly, router settings correct, DHCP ip reservation set (not necessary but helped some people). Ports closed. I started looking up online why it may not be working, and besides saying its the spectrum router/modem combo unit, everything I saw suggested that it was likely the modems fault, being locked down and all (no accessible gui). I wasn't even able to use my Asus RT N66R router with the default spectrum modem, it always said ISP DHCP not setup correctly. I bought a new modem (netgear cm600), and the asus router finally worked, port forwarded with it, setup static ip, ports still closed. I tried doing text tech support with spectrum and they told me to call a number for "advanced tech support" I did, and then was met with 28 minutes of: It's the router, its nothing on spectrums end.
But with everything correctly configured on my end, changing ISP's, Routers, Modems, Pc's, and it STILL doesn't work, can anyone help?