I had that happen a few times, I went out and put in a fresh battery , then again, and again. finally I ordered a new ISS board and no problems since. They do go bad. Check to see if the station is still under warranty and ask for a new replacement, that you will send them the present upon reciept. Don't use rechargeable batteries. They don't recharge in the ISS. When they discharge, you get the message. Put in a standard cr123A .