Ipad 3 not connecting to the wifi

My ipad stopped connecting to the wifi a couple of days ago. when i first got it the same thing happened,but i fixed it by updating the firmware of my router. i tried it this time but it still won't work. i've tried reseting settings as well as restoring but nothing seems to work. when i click on wifi, the wheel next to my wifi keeps spinning and doesn't stay connected. sometimes it connects but only for a few seconds then the wheel keeps spinning again.

any suggestions to how i can fix it?