Chosen Solution
Tried to charge and cleaned the contacts on the Fitbit charge 3. Also bought new cable just in case, but it does not charge and no diplay at all, it is blank screen
try putting it in the charger, and holding its power button for 8-10 seconds (I believe the button on the left) and see if a display appears. If not, it could be possible the battery is faulty. does it vibrate at all when you try to power it on?