WiFi networks appear but it does not connect

Hello, a few days ago I bought a WiiU, but it happens to me that when I try to connect to a wifi network it appears without problems and when I try to connect I get an error as if it will not find it. I have tried to connect with WPS, manually, other WiFi networks, put the console next to the router and nothing works. The only way I have been able to get internet is by cable with the wii adapter. Is there anything else I can try to fix it?