java.lang.RuntimeException: Unable to start activity ComponentInfo{com.entitcs.office_attendance/com.entitcs.office_attendance.FaceRecognitionRelated.object.FaceRecognitionActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void androidx.camera.lifecycle.ProcessCameraProvider.unbindAll()' on a null object reference
	at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2723)
	at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2784)
	at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:4609)
	at android.app.ActivityThread.-wrap19(ActivityThread.java)
	at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1531)
	at android.os.Handler.dispatchMessage(Handler.java:102)
	at android.os.Looper.loop(Looper.java:163)
	at android.app.ActivityThread.main(ActivityThread.java:6238)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:933)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void androidx.camera.lifecycle.ProcessCameraProvider.unbindAll()' on a null object reference
	at com.entitcs.office_attendance.FaceRecognitionRelated.helpers.MLVideoHelperActivity$3.onCheckedChanged(MLVideoHelperActivity.java:215)
	at android.widget.CompoundButton.setChecked(CompoundButton.java:156)
	at android.widget.ToggleButton.setChecked(ToggleButton.java:71)
	at android.widget.CompoundButton.onRestoreInstanceState(CompoundButton.java:545)
	at android.view.View.dispatchRestoreInstanceState(View.java:15780)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3239)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3239)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3239)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3239)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3239)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3239)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3239)
	at android.view.View.restoreHierarchyState(View.java:15758)
	at com.android.internal.policy.PhoneWindow.restoreHierarchyState(PhoneWindow.java:2106)
	at android.app.Activity.onRestoreInstanceState(Activity.java:1096)
	at android.app.Activity.performRestoreInstanceState(Activity.java:1051)
	at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1175)
	at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2696)
	... 10 more