Since it never worked consider returning it to the seller as a DOA. If you want to pursue this then call the seller and see if they want to avoid the return. It's defective on arrival so use that as the reason for return.
I have a samsung slim TV 7 While I am trying to connect wifi connection
network-wireless network-network setup-select network name-enter your wifi password-security key
my password contains 7 characters but while i am typing 2 characters the screen disappearing