I need to modified my angular.json file

"serve": { "builder": "ngx-build-plus:dev-server", "options": { "browserTarget": "myAppName:build" }, "configurations": { "production": { "browserTarget": "myAppName:build:production" }, "development": { "browserTarget": "myAppName:build:development" } }, "defaultConfiguration": "development" },

Also added below in architect-> build -> configurations section

"development": { "optimization": false, "sourceMap": true, "namedChunks": true, "extractLicenses": false, "vendorChunk": true, "buildOptimizer": false }