Stick up cam 2nd gen, stopped working

Hi, I've had a the camera for a year, outside. It stopped working about a week ago, stating loss WiFi signal. I went up the ladder to look (after leaving it a week) to try and reconnect it, but the camera is completely dead. I switched batteries, but the blue light flashes once then dead. I have brought the camera inside and connected to the mains, it still blue light flashes for three seconds then goes off and it's completely dead.... Any help? I've tried all the holding the orange button to reset it, but nothing