Remove the battery and press the ON/OFF button while the battery is out. Place the battery back into the Snuza Go. Do not switch the unit ON. Does the Snuza Go start alarming with the battery light flashing red? If yes, Replace the battery if the Snuza Go has been used extensively for a long period of time. If the battery has recently been replaced contact a Representative if the Go is still under the 12 month guarantee. contact Customer Care by completing the form on the contact us page.