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/**
     *
     * @param storeID
     * @param customerDocIdList
     * @param groupName
     * @param dataOperationCompletionListener
     */
    @Override
    public void tagGroupIntoCustomers(String storeID, ArrayList<String> customerDocIdList,final String groupName, final DataOperationCompletionListener dataOperationCompletionListener) {
        //Get a new Write batch
        WriteBatch writeBatch = billerFirestoreDB.batch();
        DocumentReference customerDocumentReference = null;
        //Reading Selected customer which is add in to a group
        for (int customerId = 0; customerId < customerDocIdList.size(); customerId++) {
            //Create reference of each customer
            customerDocumentReference = billerFirestoreDB.collection(BillConstants.VENDORS_CUSTOMER).document(storeID).collection(BillConstants.CUSTOMERS).document(customerDocIdList.get(customerId));
           //Update particular reference,fieldsKey,fieldValue
            writeBatch.update(customerDocumentReference, BillConstants.TAG_GROUP, groupName);
        }
        //commit batch
        writeBatch.commit().addOnCompleteListener(new OnCompleteListener<Void>() {
            @Override
            public void onComplete(@NonNull Task<Void> task) {
                dataOperationCompletionListener.operationCompleted(true);
            }
        });

    }