Webpack npm ERR Missing script: build; (WINDOWS 10) - node.js

Question

My bf and I were making a haiku checker during school today. Everything was working fine but when I cloned his repo i'm getting a "npm ERR! missing script: build;" on my windows 10 PC
Any help will be much appreciated and I can provide more info
Additional errors
npm ERR! Haiku#1.0.0 start: `npm run build; webpack-dev-server --open --mode development`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the Haiku#1.0.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
Here is my package.json
{
"name": "Haiku",
"version": "1.0.0",
"description": "",
"main": "index.js",
"scripts": {
"test": "karma start karma.conf.js",
"build": "webpack --mode development",
"start": "npm run build; webpack-dev-server --open --mode development",
"lint": "eslint src/*.js --fix"
},
"keywords": [],
"author": "",
"license": "ISC",
"devDependencies": {
"babel-core": "^6.26.0",
"babel-loader": "^7.1.3",
"babel-preset-es2015": "^6.24.1",
"clean-webpack-plugin": "^0.1.18",
"css-loader": "^0.28.10",
"eslint": "^4.18.2",
"eslint-loader": "^2.0.0",
"html-webpack-plugin": "^3.0.6",
"jasmine": "^3.1.0",
"jasmine-core": "^2.99.0",
"karma": "^2.0.0",
"karma-chrome-launcher": "^2.2.0",
"karma-cli": "^1.0.1",
"karma-jasmine": "^1.1.1",
"karma-jasmine-html-reporter": "^0.2.2",
"karma-jquery": "^0.2.2",
"karma-webpack": "^2.0.13",
"style-loader": "^0.20.2",
"uglifyjs-webpack-plugin": "^1.2.2",
"webpack": "^4.0.1",
"webpack-cli": "^2.0.9",
"webpack-dev-server": "^3.1.0"
},
"dependencies": {
"bootstrap": "^4.0.0",
"jquery": "^3.3.1",
"popper.js": "^1.14.1",
"syllable": "^3.0.0"
}
}