Debugging "ContactsList" Output Nothing

[shawon0709]

Hello

I tried to debug the following is showing at console

Exception: Field currentActivity or type signature not found
UnityEngine._AndroidJNIHelper.GetFieldID (System.IntPtr jclass, System.String fieldName, System.String signature, System.Boolean isStatic) (at <73adbd79bdb94a0ba2fcbcb79f3a9be2>:0)
UnityEngine.AndroidJNIHelper.GetFieldID (System.IntPtr javaClass, System.String fieldName, System.String signature, System.Boolean isStatic) (at <73adbd79bdb94a0ba2fcbcb79f3a9be2>:0)
UnityEngine._AndroidJNIHelper.GetFieldID[ReturnType] (System.IntPtr jclass, System.String fieldName, System.Boolean isStatic) (at <73adbd79bdb94a0ba2fcbcb79f3a9be2>:0)
UnityEngine.AndroidJNIHelper.GetFieldID[FieldType] (System.IntPtr jclass, System.String fieldName, System.Boolean isStatic) (at <73adbd79bdb94a0ba2fcbcb79f3a9be2>:0)
UnityEngine.AndroidJavaObject._GetStatic[FieldType] (System.String fieldName) (at <73adbd79bdb94a0ba2fcbcb79f3a9be2>:0)
UnityEngine.AndroidJavaObject.GetStatic[FieldType] (System.String fieldName) (at <73adbd79bdb94a0ba2fcbcb79f3a9be2>:0)
Contacts.LoadContactList (System.Action _onDone, System.Action`1[T] _onFailed) (at Assets/Contacts/Contacts.cs:62)
ContactsListGUI.Start () (at Assets/Contacts/ContactsListGUI.cs:25)

I don't know why this happens, please help