There are a few different reasons this might have happened. The most common is that you have run out of data. You can log onto my.simhero.com to check if you still have data. Also try checking your batteries. Next, your SD care might be full. There is a setting on the camera that will allow you to have the oldest pictures on your SD card over written by the new picture, making it so that your SD card will never be full. To turn this setting on follow these steps. First be in the setup screen. Now hit the "Menu" button- scroll across the top to "other", now scroll down to "SD cycle", press ok and now scroll down to the on and select on.