Select the Fitbit application on your phone.
Select your profile on the very top-left of the screen. (You may or not have uploaded a profile picture of yourself here.)
Scroll down until you find "App Settings," and select it.
Deselect "Set Automatically" to stop your Fitbit application from auto-setting your time.
Because of the Fitbit Charge 3 and Charge 4's compact nature, Fitbit has crammed as much as they could into the small amount screen space available on the Charge, making it tricky to do simple tasks like changing the time. This includes the reset feature. I've had a Fitbit Charge 3 and now a Fitbit Charge 4, and I still make discoveries from time to time about a new app or feature I never knew existed. So let us help guide you through the metaphorical maze that is the Fitbit Charge 3 and Charge 4, and get you to that reset button pronto!