@Tony Setting NAS as the DMZ didn't help. And I've found that I can't redirect not only ports 80 and 443 for the NAS, but no other port on any device, they're all still closed.

I just bought new Archer AX73 and it seems that port forwarding doesn't work. When I open ie. port 9000 in port forwarding and use https://www.yougetsignal.com/tools/open-ports/ to test it, it always...