Hi,
I’m by no means an IT expert but I do have a network of more than 12 PCs, ( Windows, Linux, and Mac ) that I manage at home. My suggestion would be to “RESET” the router. This is different from turning it off and back on. Typically there is a small push button, usually on the back of the router, that you push for anywhere from 3 to 10 seconds. This usually resets the router to the settings it left the factory with
I saw that reset button ~ I will try that to see what happens. Should I also hit the reset button on the cable modem?
Wait . . . the new router does not work either ~ should I try the reset button on that one also?