我正试图从github运行一个项目，但运行时遇到了这些错误

Execution failed for task ':app:processDebugResources'.
> A failure occurred while executing com.android.build.gradle.internal.tasks.Workers$ActionFacade
   > Android resource linking failed
     C:\Users\arad\AndroidStudioProjects\testapp\app\build\intermediates\packaged_manifests\debug\AndroidManifest.xml:16: AAPT: error: resource style/Theme.testapp(aka com.example.testapp:style/Theme.testapp) not found.

     C:\Users\arad\AndroidStudioProjects\testapp\app\build\intermediates\packaged_manifests\debug\AndroidManifest.xml:26: AAPT: error: resource style/Theme.testapp.NoActionBar (aka com.testapp.testapp:style/Theme.testapp.NoActionBar) not found.

以下是主\androidmanife.xml文件：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.testapp">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.testapp">
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name"
            android:theme="@style/Theme.testapp.NoActionBar">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>