Not syncing and rebooting device

[Fiona123456]

Hello I need help,I have several issues with my Fitbit charge 3. 
The first problem was the time was lagging.  
I then realised that my Fitbit was not syncing.  
I then also realised my Bluetooth was not picking it up.  
so I took to the Fitbit help and threads.  
I have tried turning Bluetooth of and off, deleting my Fitbit app and logging out and setting it up as a new device.  
I finally read a thread that said reboot your device.  
the problem I have now.  It’s again I’ve read a thread and charging for and pressing for 15 seconds.  But when I press the screen is black it vibrates and nothing happens.  
I’m at a loss as the Fitbit is only 2 years old and after a year the black lines across the screen were happening but now I think there is nothing I can do. M thanks for any suggestions. 

[Odyssey13]

when there is someone available, chat is an option. Phone or Twitter works well, too.

https://myhelp.fitbit.com/s/support?language=en_US 

Support is limited by the number of representatives available at a given time and the hours of operation. Chat lines are open when they have live help.
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Other contact options:

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[willjoe]

Bluetooth and turn Bluetooth off and back on. Turn your phone or tablet off and back on. Uninstall and reinstall the Fitbit app. If your Fitbit scale won't sync after you reinstall the app, log in to your Fitbit account on a different phone or tablet and try to sync

Regards,