Can't connect wirelessly only through Ethernet cable

Changed routers and my old router's ssid was still showing up. someone suggested online that i uninstall/reinstall my wireless adapter. And so I did but now I can't connect without ethernet cable.

Ihave it enabled through fn + f2 still doesnt work.  I tried downloading drivers through "Dell Drivers & Downloads" with my  service tag but nothing worked.

I'm using dell inspiron m5040. Please help. I'll appreciate it