code: public Data txnCommitPollBackup(long itemId) {
          TxQueueItem item = txMap.remove(itemId);
          if (item == null) {
              logger.warning("txnCommitPoll operation-> No txn item for itemId: " + itemId);
              return null;
          }
          if (store.isEnabled()) {
              try {
                  store.delete(item.getItemId());
              } catch (Exception e) {
                  logger.severe("Error during store delete: " + item.getItemId(), e);
              }
          }
          return item.getData();
      }
docs: Commits the effects of the {@link #txnPollReserve(long, String)}}. Also deletes the item data from the queue
  data store if it is configured and enabled.
  
  @param itemId the ID of the item which was polled inside a transaction
  @return the data of the polled item
  @throws HazelcastException if there was any exception while removing the item from the queue data store