Set Up and Dismiss Alarms
Fitbit's app lets you set up to eight alarms that can wake you once, or repeat on certain days. If you have a Charge 2, you don't actually have to go into your app to disable an alarm.
For All Fitbits:
1. Select your device under your account settings
2. Tap on Silent Alarm to set up your alarms.
If You Have A Charge 2:
1. Press the button on the Fitbit until an icon with a bell appears.
2. Press and hold the button until the bell icon above the alarm time is crossed out, and your alarm is disabled.
3. Tap the Charge 2's screen to navigate through your next alarms. You can long-press the button to disable those, too.