c3700 Troubleshooting Wifi

Hi there,

My internet connection has been suffering the past few months, and finally the wifi stopped working the other day. 
My service provider indicated the trouble was with my router, so I gave it a hard reset, made certain the firmware was up to date. I get internet with an ethernet cable, but I have not been able to fix the wifi.

The router is less than a year old, does anyone have advice for me?

Thanks kindly!