I am terribly sorry to hear that you're having this issue! I would love to assist you with this issue. If you are having issues with your Nest Cam or Nest Doorbell, I would suggest that you first start by restarting it.
Restart: Keeps all your settings, and it should reconnect to the same Wi-Fi network. This is helpful if it ever becomes frozen, has trouble reconnecting to the internet, or isn't working normally.