@jthirasilpa just do this… get my version of the module
cd ~/MagicMirror/modules
mv MMM-NetworkScanner MMM-NetworkScanner.original
git clone https://github.com/sdetweil/MMM-NetworkScanner
cd MMM-NetworkScanner
npm install
cd ~/MagicMirror/config
nano config.js
add the following line to the config section of the network scanner module
Password: '??????', // where '?????' is you password in quotes, for example 'raspberry', note the trailing comma
ctrl-o at save the config.js
ctrl-x to exit nano
Restart your MM