This error code appears when your camera has no more room to take pictures. This can be due to a memory card being full or missing. While the text will not say anything about lack of space, you will see a [ 0 ] symbol next to your camera battery sign in the Entagged app:
To fix this, make sure your memory card is inserted. If so, make sure to either switch to an empty memory card, or delete some photos from your camera to free up space.