voice rocoginition took same text in multiple time

[son2017]

i have an issue with PartialResultsListener its working fine but while runnng the code its tack same message multiple time any idea the code is blow:

final ai.api.PartialResultsListener partialResultsListener = new PartialResultsListener() {
@OverRide
public void onPartialResults(List partialResults) {

            Toast.makeText(ChatActivity.this, partialResults.get(0), Toast.LENGTH_SHORT).show();

            ChatMessage chatMessage = new ChatMessage(partialResults.get(0), true);
            chatMessages.add(chatMessage);
            listView.setSelection(adapter.getCount()-1);
            adapter.notifyDataSetChanged();


        }
    };

    if (aiService instanceof GoogleRecognitionServiceImpl){
        ((GoogleRecognitionServiceImpl)aiService).setPartialResultsListener(new PartialResultsListener() {
            @Override
            public void onPartialResults(List<String> partialResults) {
                if (partialResultsListener!=null){
                    partialResultsListener.onPartialResults(partialResults);
                }
            }
        });
    }

its display same command multiple time for instance if i say hello then its display hello three time.