Unauthorized while linking changeset from SCM to JIRA using REST API

public Boolean createLink(String jiraUrl) {

#####

String linkEndpoint = fTeamRepository.getRepositoryURI()

+ "service/com.ibm.team.scm.common.internal.rest.IScmRestService2/addChangeRequests";

String responseBody = "changeSetItemId=" + fChangeSet.getItemId().getUuidValue() + "&targetOslcResourceUris="

+ URLEncoder.encode(jiraUrl) + "&targetLabels=" + "Test%20scm%20to%20jira%20linking"

+ "&targetRepoIds=&targetRepositoryURIs=";

HttpURLConnection linkConn = (HttpURLConnection) new URL(linkEndpoint).openConnection();

linkConn.setRequestMethod("POST");

byte[] decodedBytes = Base64.getDecoder().decode(encodedKey.trim());

String pswd = new String(decodedBytes);

String auth = fTeamRepository.loggedInContributor().getUserId() + ":" + pswd;

String encodedAuth = Base64.getEncoder().encodeToString((auth).getBytes());

linkConn.setDoOutput(true);

linkConn.setInstanceFollowRedirects(true);

linkConn.setRequestProperty("Authorization", "Basic " + encodedAuth);

linkConn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");

linkConn.setRequestProperty("accept", "text/json");

linkConn.setRequestProperty("x-requested-with", "XMLHttpRequest");

linkConn.setRequestProperty("X-Jazz-CSRF-Prevent", "1");

//linkConn.setRequestProperty("Cookie", cookies);

try (OutputStream os = linkConn.getOutputStream()) {

byte[] input = responseBody.getBytes("utf-8");

os.write(input, 0, input.length);

}

int responseCode = linkConn.getResponseCode();

String responseMsg = linkConn.getResponseMessage();

System.out.println("Response: " + responseCode + " " + responseMsg);

####

}