NativeScript "tns run ios" failed

gistfile1.txt

1: 'iPhone6,1' iOS b54af16acfe895f01eb93add04448a74d2f7bb2b
Longs-MacBook-Pro:hello-world longpham$ tns run ios --device b54af16acfe895f01eb93add04448a74d2f7bb2b
Project successfully prepared
Build settings from command line:
    ARCHS = armv7 arm64
    CONFIGURATION_BUILD_DIR = /Users/longpham/Projects/hello-world/platforms/ios/build/device
    SDKROOT = iphoneos8.4
    SHARED_PRECOMPS_DIR = /Users/longpham/Projects/hello-world/platforms/ios/build/sharedpch
    VALID_ARCHS = armv7 arm64

Build settings from configuration file '/Users/longpham/Projects/hello-world/platforms/ios/helloworld/build.xcconfig':
    CODE_SIGN_IDENTITY = iPhone Developer

=== BUILD TARGET helloworld OF PROJECT helloworld WITH CONFIGURATION Debug ===

Check dependencies
Code Sign error: No code signing identities found: No valid signing identities (i.e. certificate and private key pair) matching the team ID “(null)” were found.
CodeSign error: code signing is required for product type 'Application' in SDK 'iOS 8.4'

** BUILD FAILED **


The following build commands failed:
	Check dependencies
(1 failure)
Command xcodebuild failed with exit code 65
# run ios
┌──────────────────────────────┬───────────────────────────────────────────┐
│ Usage                        │ Synopsis                                  │
│ Run on all connected devices │ $ tns run ios [--release] [--justlaunch]  │
│ Run on a selected connected  │ $ tns run ios [--device <Device ID>] [-   │
│ device                       │ -release] [--justlaunch]                  │
│ Start an emulator and run    │ $ tns run ios --emulator [<Emulator       │
│ the app inside it            │ Options>] [--release]                     │
└──────────────────────────────┴───────────────────────────────────────────┘

Runs your project on a connected iOS device or in the iOS Simulator, if configured. This is shorthand for prepare, build, and deploy.

IMPORTANT: Before building for iOS device, verify that you have configured a valid pair of certificate and provisioning profile on your OS X system. 

### Options

    * --device - Specifies a connected device on which to run the app. 
    * --emulator - If set, runs the app in a native emulator for the target platform, if configured. When set, you can also set any other valid combination of emulator options as listed by $ tns help emulate ios. You cannot use --device and --emulator simultaneously.
    * --release - If set, produces a release build. Otherwise, produces a debug build.
    * --justlaunch - If set, does not print application output on the console. Otherwise prints the application output on the console.

### Attributes

    * <Device ID> is the index or name of the target device as listed by $ tns device ios 
    * <Emulator Options> is any valid combination of options as listed by $ tns help emulate ios