General :: LG-E400 WiFi Will Not Turn On?

LG-E400 one week ago. The phone is running v2.3.6. It is running on Spain's tuenti network and up until two days ago it was running fine in every way. The problem now is that it will not allow 'turn on' the wifi, let alone connect or use it. When I check the 'Turn on Wi-Fi' box in Settings>Wireless & networks it tells me that it is turning on, and on occasion tells me that it is turned on, but invariably it 'turns off' within 10 seconds or less. When I turn on wifi using the icon int he pull down menu it likewise changes colour to signify that it is on, but turns off of its own accord within a few seconds. The wifi had worked perfectly until a few days ago, and nothing has changed since that time to the best of my knowledge. It is a new phone, has been used carefully, and there have been no other issues with it.