Hello, it sounds like your camera has failed. If it is less than 1 year old then Google will help you under the warranty. If it is not the I'm afraid you are on your own. You may just want to buy a used cam from eBay. I have done that a few times over the years and I have had good luck with used cameras. Here is the link to open a support ticket if you want to speak with a Google Tech person....
https://support.google.com/googlenest/gethelp
