I got the same behaviour and I did everything that Nitendo support describe but without success.
Then I start reading my router manual and that gives me an idea.
My home network, wasn't folowing the Private IP Address Ranges standart rule. (10.0.0.0-10.255.255.255; 172.16.0.0-172.31.255.255; 192.168.0.0-192.168.255.255)
Then now the problem is solved!
Hope that helps!!!