Connection error with infura "UnknownHostException"

Questions
1

Hello, I currently have a java method that obtains the data of a transaction with the TxHash, after using the method for a while it presents the following error and I can not receive the input data of that transaction:
“java.util.concurrent.ExecutionExc eption: java.net.UnknownHostException: rinkeby.infura.io”

This is my code:
Connection Infura

 @WebMethod(operationName = "ObtenerDatosByHash")
    public ArrayList<String> ObtenerDatosByHash(@WebParam(name = "txHash") String txHash) throws IOException, InterruptedException, ExecutionException, DecoderException, NoSuchMethodException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, ClassNotFoundException, URISyntaxException, JSONException {

        Web3j web3 = Web3j.build(new HttpService("https://rinkeby.infura.io/v3/xxxxxxxx"));
        Conexion conexion = new Conexion();

Method Blockchain

public ArrayList obtenerByHash(Web3j web3, String txHash) throws IOException, InterruptedException, ExecutionException, DecoderException, NoSuchMethodException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, ClassNotFoundException, URISyntaxException, JSONException {
Conexion conexion = new Conexion();
String inputData = null;

    System.out.println("WebService-Testnet-20");
    
    Optional<Transaction> tx = web3.ethGetTransactionByHash(txHash).sendAsync().get().getTransaction();

    if (tx.isPresent()) {
        inputData = tx.get().getInput();
    }

    ArrayList<String> lista = new ArrayList<>();
2

That error indicates a DNS lookup failure. Are you running this from a node with a reliable network connection and DNS configuration? If you are running with a DNS cache server in between your test device and the internet that may be the cause of this issue.

3