If you have the Wi-Fi calling (TMO) feature in use in your phone, please clear the temporary files with the Storage Check app when the Wi-Fi is turned off. This will vacate more space.

  1. Update the Storage Check app (to version 1.3.0.20 or higher, when available). 
  2. Set Wi-Fi off (Settings > WLAN > Toggle off).
  3. Launch Storage Check.
  4. Press the Clear button to delete the files.
  5. Update your Lumia to Black.

Note: You may also have too little space on the user disk. Please move some content to the cloud or SD card to vacate more space.