It is not clear what the basis of the digital licence is, if the Windows licence was pre-installed by Lenovo on that device, then there is an OEM licence stored on the motherboard and any time you re-install Windows, activation would be automatic.
Click your Start Button, type cmd then right click Command Prompt and choose 'Run as Administrator'
Run or paste this command and hit Enter:
slmgr.vbs /dlv
Please post a screenshot of the resulting dialog