diff --git a/src/main/java/fr/delthas/skype/WebConnector.java b/src/main/java/fr/delthas/skype/WebConnector.java
index 032c3ac..dbda162 100644
--- a/src/main/java/fr/delthas/skype/WebConnector.java
+++ b/src/main/java/fr/delthas/skype/WebConnector.java
@@ -118,7 +118,7 @@ private User updateUser(JSONObject userJSON, boolean newContactType) throws Pars
     String userAvatarUrl = null;
     try {
       if (!newContactType) {
-        userUsername = userJSON.getString("username");
+        userUsername = userJSON.optString("username");
         userFirstName = userJSON.optString("firstname", null);
         userLastName = userJSON.optString("lastname", null);
         userMood = userJSON.optString("mood", null);
@@ -220,6 +220,7 @@ private Response sendRequest(Method method, String apiPath, boolean absoluteApiP
     logger.finest("Sending " + method + " request at " + url);
     if (skypeToken != null) {
       conn.header("X-Skypetoken", skypeToken);
+      conn.header("Accept", "application/json");
     } else {
       logger.fine("No token sent for the request at: " + url);
     }