no type arguments expected for fun getValue: Any?

Question

i'm trying to implement a code sample from Firebase Doc that Listen for child events,

val childEventListener = object : ChildEventListener {
override fun onChildAdded(dataSnapshot: DataSnapshot, previousChildName: String?) {
    Log.d(TAG, "onChildAdded:" + dataSnapshot.key!!)

    // A new comment has been added, add it to the displayed list
    val comment = dataSnapshot.getValue<Comment>() // error line

    // ...
}
...
...

when i tried it for my firebase, Android studio hints an error on val comment = dataSnapshot.getValue<Comment>()

Error: no type arguments expected for fun getValue: Any?

Can someone please explain the meaning of this error and how to get around it.