Thought I had posted this a few days back but cannot find my post. Like you my Blaze was working one day and then had a dimly lit greyish blank screen. It keeps vibrating as if it were restarting but does NOTHING. This is what I tried so far without success to get my Blaze to connect to app to try suggestions like changing the face:
1) restart Blaze, restart phone, turn off Bluetooth then turn back on, etc. BUT can never sync to app
2) charge Blaze for more than 24 hours
3) try different chargers
4) try different phone running earlier Android OS
5) delete phone pairing and restart Bluetooth to scan again. Sometimes it finds it, sometimes it finds something but just shows MAC address but could not get it to sync to phone app
6) put it in charger and connect to computer to see if can be recognized, computer makes the device attached sound followed almost immediately by the disconnect sound
7) deleted Blaze from account and try to add to account again, each time takes a bit then says Found your tracker but then cannot connect
😎 left it off charger for 3 days to completely run down battery but it would still slightly respond even after all that time and give dim grey screen
9) tried charging from computer for 24 hours again but still cannot connect
10) tried using old Fitbit Connect program on computer but it churns without launching
So you could try some of those steps but none worked for me. Good luck
