error on start

[eskander121]

when i ran npm start i got this error in my browser:

TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined at validateString (internal/validators.js:120:11) at Object.join (path.js:1039:7) at noopServiceWorkerMiddleware (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/react-dev-utils/noopServiceWorkerMiddleware.js:14:26) at Layer.handle [as handle_request] (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/layer.js:95:5) at trim_prefix (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/index.js:328:13) at /home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/index.js:286:9 at Function.process_params (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/index.js:346:12) at next (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/index.js:280:10) at launchEditorMiddleware (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/react-dev-utils/errorOverlayMiddleware.js:20:7) at Layer.handle [as handle_request] (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/layer.js:95:5) at trim_prefix (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/index.js:328:13) at /home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/index.js:286:9 at Function.process_params (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/index.js:346:12) at next (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/index.js:280:10) at handleWebpackInternalMiddleware (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/react-dev-utils/evalSourceMapMiddleware.js:42:7) at Layer.handle [as handle_request] (/home/eskander/scalachessgui/Chess-Random-Moves/node_modules/express/lib/router/layer.js:95:5)