Apple Watches are one of the most popular tech accessories these days. You probably know a handful of people who have one (and maybe never take it off). But now Apple Watches are accidentally calling 911 and that is not a good thing.

Kansas police have finally figured out why the city’s 911 operators keep getting calls from people who refuse to speak: because the parties making the calls aren’t people. A rep for the Overland Park Police Department says investigators have determined the calls have been coming from Apple Watch users who are unaware that their electronic devices are connecting with the emergency number. “What happens is while people are moving around in their sleep or exercising, they’ll get the Apple Watch into the emergency mode,” says Overland Park Police Captain Jim Sutterby. “Without knowing it, the watch will actually call 911.”

The accidental calls have left the city’s 911 operators overwhelmed as they’ve been fielding as many as 250 per hour, Sutterby says. For its part, Apple has issued a reminder to its customers: “If you start an emergency call by accident, tap the ‘End Call’ button, then tap ‘Yes’ to confirm that you want to stop the call.”

A good rule of thumb seems to be don’t wear your watch to sleep. You don’t want the accidental call to prevent someone who needs emergency services from getting it. 911 dispatchers are required to call back any hang-up calls they receive as a precaution.

A good way to prevent this from happening is to get a case for your watch. This will protect the buttons on the side which can trigger emergency mode. Another way is to turn off SOS mode. If your watch does accidentally call 911 don’t hang up before letting them know the call was accidental. No word yet on if there will be an update to prevent apple watches from calling 911.

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