block, err := api.blockByNumberWithSenders(ctx, tx, blockNum)
	if err != nil {
		return nil, err
	}
	if block == nil {
		return nil, nil // not error, see https://github.com/erigontech/erigon/issues/1645
	}

	var txnIndex uint64
	var txn types.Transaction
	for idx, transaction := range block.Transactions() {
		if transaction.Hash() == txnHash {
			txn = transaction
			txnIndex = uint64(idx)
			break
		}
	}