Device can't connect to Wifi

My router is D-Link dir1960. The problem is i am trying to connect a tv to the network but it just can't connect to it i have already turned of mac filtering under under wireless 2.4ghz all other devices are working fine but this device can't even connect although it worked earlier the device can connect to other networks but not this one what might be wrong?

Do other devices connect?

Please copy the output of the following commands and post it here using the "Preformatted text </> " button:
Remember to redact passwords, MAC addresses and any public IP addresses you may have:

cat /etc/config/network
cat /etc/config/wireless
cat /etc/config/dhcp
cat /etc/config/firewall