So AT&T replaced our router, since our old one stopped working. I usually access it with {ip}:8123 but the ip changed since it is a new router. so i use the new ip, still wont work. I unplugged it, reset the router and nothing has worked. Except since I have configurator, I can still so {ip}:3218 and it stangely works.
Sounds like a port forwarding entry for 8123 is missing.
Op are you attempting access from inside or outside your local network? If from outside the suggestion above makes sense although it is odd the 3128 forward was carried over.
If internal, what is the browser reporting?
Anything in the error log? Something could have stopped HA from starting.
Config error. Verify it is correct and not preventing ha frontend d from coming up.
Log into router and verify the IP of HA server
EDIT
I know you see config but I still think you should verify IP since you say it’s changed after network changes
Try clearing the browser cache.