My headphones won't connect.

Hi, I have a Blackshark v2 Hyperspeed headset and the dongle has stopped working twice, at least after a couple of the initial suggestions. A very faint green light shows for a second before Windows tells me it doesn't recognize the USB device and won't connect my headset. I've tried Synapse, uninstalling options, developing software, pairing utilities, and everything else suggested, but without success. So I'm showing you what to do because I can't find where to buy a replacement dongle either. The headset is about 1.5 years old, so I don't want to replace it completely.