unable to run the npm start

[kiruthika204]

this is my error
so many times i'm facing this issues.
i didn't know to get a solution
ERROR in ./src/app/services/auth.service.ts
[1] Module not found: Error: Can't resolve '../../../build/contracts/UserRegistry.json' in '/home/kiruthika/newdapp/supply-chain/src/app/services'
[1] resolve '../../../build/contracts/UserRegistry.json' in '/home/kiruthika/newdapp/supply-chain/src/app/services'
[1] using description file: /home/kiruthika/newdapp/supply-chain/package.json (relative path: ./src/app/services)
[1] Field 'browser' doesn't contain a valid alias configuration
[1] after using description file: /home/kiruthika/newdapp/supply-chain/package.json (relative path: ./src/app/services)
[1] using description file: /home/kiruthika/newdapp/supply-chain/package.json (relative path: ./build/contracts/UserRegistry.json)
[1] no extension
[1] Field 'browser' doesn't contain a valid alias configuration
[1] /home/kiruthika/newdapp/supply-chain/build/contracts/UserRegistry.json doesn't exist
[1] .ts
[1] Field 'browser' doesn't contain a valid alias configuration
[1] /home/kiruthika/newdapp/supply-chain/build/contracts/UserRegistry.json.ts doesn't exist
[1] .js
[1] Field 'browser' doesn't contain a valid alias configuration
[1] /home/kiruthika/newdapp/supply-chain/build/contracts/UserRegistry.json.js doesn't exist
[1] as directory
[1] /home/kiruthika/newdapp/supply-chain/build/contracts/UserRegistry.json doesn't exist
[1] [/home/kiruthika/newdapp/supply-chain/build/contracts/UserRegistry.json]
[1] [/home/kiruthika/newdapp/supply-chain/build/contracts/UserRegistry.json.ts]
[1] [/home/kiruthika/newdapp/supply-chain/build/contracts/UserRegistry.json.js]
[1] [/home/kiruthika/newdapp/supply-chain/build/contracts/UserRegistry.json]
[1] @ ./src/app/services/auth.service.ts 13:19-72
[1] @ ./src/app/app.module.ts
[1] @ ./src/main.ts
[1] @ multi webpack-dev-server/client?http://localhost:4200 ./src/main.ts
[1] ERROR in ./src/app/services/contract.service.ts
[1] Module not found: Error: Can't resolve '../../../build/contracts/OrderRegistry.json' in '/home/kiruthika/newdapp/supply-chain/src/app/services'
[1] resolve '../../../build/contracts/OrderRegistry.json' in '/home/kiruthika/newdapp/supply-chain/src/app/services'
[1] using description file: /home/kiruthika/newdapp/supply-chain/package.json (relative path: ./src/app/services)
[1] Field 'browser' doesn't contain a valid alias configuration
[1] after using description file: /home/kiruthika/newdapp/supply-chain/package.json (relative path: ./src/app/services)
[1] using description file: /home/kiruthika/newdapp/supply-chain/package.json (relative path: ./build/contracts/OrderRegistry.json)
[1] no extension
[1] Field 'browser' doesn't contain a valid alias configuration
[1] /home/kiruthika/newdapp/supply-chain/build/contracts/OrderRegistry.json doesn't exist
[1] .ts
[1] Field 'browser' doesn't contain a valid alias configuration
[1] /home/kiruthika/newdapp/supply-chain/build/contracts/OrderRegistry.json.ts doesn't exist
[1] .js
[1] Field 'browser' doesn't contain a valid alias configuration
[1] /home/kiruthika/newdapp/supply-chain/build/contracts/OrderRegistry.json.js doesn't exist
[1] as directory
[1] /home/kiruthika/newdapp/supply-chain/build/contracts/OrderRegistry.json doesn't exist
[1] [/home/kiruthika/newdapp/supply-chain/build/contracts/OrderRegistry.json]
[1] [/home/kiruthika/newdapp/supply-chain/build/contracts/OrderRegistry.json.ts]
[1] [/home/kiruthika/newdapp/supply-chain/build/contracts/OrderRegistry.json.js]
[1] [/home/kiruthika/newdapp/supply-chain/build/contracts/OrderRegistry.json]
[1] @ ./src/app/services/contract.service.ts 14:20-74
[1] @ ./src/app/app.module.ts
[1] @ ./src/main.ts
[1] @ multi webpack-dev-server/client?http://localhost:4200 ./src/main.ts
[1]
webpack failed