macOS Sierra not able to restore from recovery

How to reinstall macOS this will require a functioning and active Internet Connection

Best Results are via Ethernet Cable to Router

Follow these guidelines during installation:

• If the installer asks to unlock your disk, enter the password you use to log in to your Mac.
• If the installer doesn't see your disk, or it says that it can't install on your computer or volume, you might need to erase your disk first.
• If the installer offers you the choice between installing on Macintosh HD or Macintosh HD - Data, choose Macintosh HD.

In Recovery mode have you tried Disk Utility's Disk First Aid yet?