diff --git a/app/src/main/java/com/example/notifyservice/MainActivity.java b/app/src/main/java/com/example/notifyservice/MainActivity.java
index 065e249..499ea46 100644
--- a/app/src/main/java/com/example/notifyservice/MainActivity.java
+++ b/app/src/main/java/com/example/notifyservice/MainActivity.java
@@ -363,11 +363,11 @@ public class MainActivity extends AppCompatActivity implements PostRequestCallba
     @Override
     public void onPostResponse(JSONObject result) {
         try {
-            if(!result.getString("hash").isEmpty()) // STATIC
+            if(!result.has("hash")) // STATIC
                 currentHash = result.getString("hash"); // STATIC
-            if(!result.getString("key").isEmpty()) // STATIC
+            if(!result.has("key")) // STATIC
                 setKey(getBaseContext(), result.getString("key")); // STATIC
-            if(!result.getString("timeout").isEmpty()) { // STATIC
+            if(!result.has("timeout")) { // STATIC
                 codeTimeout = result.getDouble("timeout"); // STATIC
                 Timer timer = new Timer();
                 timer.schedule(new TimerTask() {