Android Error - java.security.cert.CertPathValidatorException: Trust anchor for certification path not found

Question

So I've been stuck on this for a while. The call worked and then it didn't after a week. Makes me wonder whats going on. I got the certificate (also tried the chain, from the site - PEM format) but this error persists.

Below is my code

 public static HttpsURLConnection setUpHttpsConnection(String urlString, Context ctx)
     {
         try
         {
             CertificateFactory cf = CertificateFactory.getInstance("X.509");
             InputStream caInput = new BufferedInputStream(ctx.getAssets().open("servercert.pem"));
             Certificate ca = cf.generateCertificate(caInput);
             System.out.println("ca=" + ((X509Certificate) ca).getSubjectDN());

             // Create a KeyStore containing our trusted CAs
             String keyStoreType = KeyStore.getDefaultType();
             KeyStore keyStore = KeyStore.getInstance(keyStoreType);
             keyStore.load(null, null);
             keyStore.setCertificateEntry("ca", ca);


             // Create a TrustManager that trusts the CAs in our KeyStore
             String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
             TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
             tmf.init(keyStore);
             

             // Create a TrustManager that trusts the CAs in our KeyStore
             String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
             TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
             tmf.init(keyStore);

             // Create an SSLContext that uses our TrustManager
             SSLContext context = SSLContext.getInstance("TLS");
             context.init(null, tmf.getTrustManagers(), null);

             

             // Tell the URLConnection to use a SocketFactory from our SSLContext
             URL url = new URL(urlString);
             URLEncoder.encode(url.toString(), "UTF-8");


             HttpsURLConnection urlConnection = (HttpsURLConnection)url.openConnection();

             urlConnection.setSSLSocketFactory(context.getSocketFactory());

             return urlConnection;
         }
         catch (Exception ex)
         {
             Log.e(TAG, "Failed to establish SSL connection to server: " + ex.toString());
             return null;
         }
    }

and in a task called from MainActivity, I have

HttpsURLConnection myConnection = setUpHttpsConnection(endpoint.toString(), ctx);

//end point is - www.alphavantage.co/query?function=GLOBAL_QUOTE&symbol=NVDA&datatype=json&apikey=U89XCI9ILUCICTP1

//fails on the line below
 if (myConnection.getResponseCode() == 200) {
                InputStream responseBody = myConnection.getInputStream();

It fails on if (myConnection.getResponseCode() == 200) {

with the stacktrace

W/System.err: javax.net.ssl.SSLHandshakeException: java.security.cert.CertPathValidatorException: Trust anchor for certification path not found. W/System.err: at com.android.org.conscrypt.SSLUtils.toSSLHandshakeException(SSLUtils.java:362) W/System.err: at com.android.org.conscrypt.ConscryptEngine.convertException(ConscryptEngine.java:1134) W/System.err: at com.android.org.conscrypt.ConscryptEngine.readPlaintextData(ConscryptEngine.java:1089) W/System.err: at com.android.org.conscrypt.ConscryptEngine.unwrap(ConscryptEngine.java:876) W/System.err: at com.android.org.conscrypt.ConscryptEngine.unwrap(ConscryptEngine.java:747) W/System.err: at com.android.org.conscrypt.ConscryptEngine.unwrap(ConscryptEngine.java:712) W/System.err: at com.android.org.conscrypt.ConscryptEngineSocket$SSLInputStream.processDataFromSocket(ConscryptEngineSocket.java:849) W/System.err: at com.android.org.conscrypt.ConscryptEngineSocket$SSLInputStream.access$100(ConscryptEngineSocket.java:722) W/System.err: at com.android.org.conscrypt.ConscryptEngineSocket.doHandshake(ConscryptEngineSocket.java:238)

I have set the networkconfig.xml to point to the certificate and also set up the manifest file.

Thanks

Keep getting the same error.