08-23 19:37:04.425 22801-22801/com.example.app16 E/AndroidRuntime: FATAL EXCEPTION: main
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.app16/com.example.app16.MainActivity}: java.lang.IllegalStateException: WorkManager is already initialized.  Did you try to initialize it manually without disabling WorkManagerInitializer? See WorkManager#initialize(Context, Configuration) or the class levelJavadoc for more information.
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2234)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
        at android.app.ActivityThread.access$600(ActivityThread.java:181)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1332)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:153)
        at android.app.ActivityThread.main(ActivityThread.java:5037)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:821)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
        at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.IllegalStateException: WorkManager is already initialized.  Did you try to initialize it manually without disabling WorkManagerInitializer? See WorkManager#initialize(Context, Configuration) or the class levelJavadoc for more information.
        at androidx.work.impl.WorkManagerImpl.initialize(WorkManagerImpl.java:167)
        at androidx.work.WorkManager.initialize(WorkManager.java:203)
        at com.example.app16.MainActivity.onCreate(MainActivity.java:22)
        at android.app.Activity.performCreate(Activity.java:5020)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2198)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
        at android.app.ActivityThread.access$600(ActivityThread.java:181)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1332)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:153)
        at android.app.ActivityThread.main(ActivityThread.java:5037)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:821)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
        at dalvik.system.NativeStart.main(Native Method)