i have the same problem, and this happen when i restarted my device, then refused to power on. if trying to press power button it just light-up showing NOKIA for few second and get off.
And then I flashed it with both EMMC & OS, and worked fine. Now when i checked the network was not available.
and if i go to setting then "Phone" it pop-up message saying "cellular network not available", and also i can't send any file like; picture etc. via Bluetooth!

Any help will be appreciated.