heroku Module build failed (from ./node_modules/babel-loader/lib/index.js) code example

Example: Module not found: Can't resolve 'C:\Users\{user}\Documents\React apps\{app-name}\node_modules\react-scripts\node_modules\babel-loader\lib\index.js'

// run the following command in your terminal

npm install babel-loader --save-dev
// this may take up to 15 mins, grab a cup of coffee!