Age calculator app in React

Hi I have problem setting the app for GitHub pages. When I run npm run deploy ("deploy": "gh-pages -d build") it says this Error: The pattern in the "src" property didn't match any files. at Object.publish (/Users/patrikholler/workspace/age-calculator-app-main/node_modules/gh-pages/lib/index.js:111:7) at /Users/patrikholler/workspace/age-calculator-app-main/node_modules/gh-pages/bin/gh-pages.js:12:13 at new Promise (<anonymous>) at publish (/Users/patrikholler/workspace/age-calculator-app-main/node_modules/gh-pages/bin/gh-pages.js:10:10) at /Users/patrikholler/workspace/age-calculator-app-main/node_modules/gh-pages/bin/gh-pages.js:140:12