java.lang.IllegalStateException: Could not execute method for android:onClick
	at androidx.appcompat.app.l$a.onClick(SourceFile)
	at android.view.View.performClick(View.java:5619)
	at android.view.View$PerformClick.run(View.java:22298)
	at android.os.Handler.handleCallback(Handler.java:754)
	at android.os.Handler.dispatchMessage(Handler.java:95)
	at android.os.Looper.loop(Looper.java:165)
	at android.app.ActivityThread.main(ActivityThread.java:6375)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:912)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:802)
Caused by: java.lang.reflect.InvocationTargetException
	at java.lang.reflect.Method.invoke(Native Method)
	... 10 more
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void n8.b.d()' on a null object reference
	at n8.a$e.a(SourceFile)
	at n8.a.c(SourceFile)
	at com.entitcs.office_attendance.camera.FaceTrackerActivity.groupAttendance(SourceFile)
	... 11 more