that means the battery is running out.
before you go buy a new tamagotchi, press the back RESET button, and download it. the cross thing that shows that your tamagotchis battery is running out, it will disappear, but then it will appear again. so download it again. i reccomend to buy a new battery after the first time the thing comes up that shows that your tamagotchi is running out of battery.
look in the instruction sheet for what kind of batteries.
hope that helped you!!
