diff --git a/src/colnod/colnodapi.cpp b/src/colnod/colnodapi.cpp
index fc283d8..8314b77 100644
--- a/src/colnod/colnodapi.cpp
+++ b/src/colnod/colnodapi.cpp
@@ -26,14 +26,26 @@ void ColnodAPI::downloadData(const Timestamp &time)
     auto login = requestLogin();
     connect(login.get(), &serversdk::Request::finished, this, [=](){
         // Get login token
-        if (!checkRequest(login)) {
+        if (login->status() != 200) {
             emit downloadDataFinished(nullptr);
             return;
         }
 
         AuthToken token;
-        token.fromJson(login->responseData());
+        auto responseData = login->responseData();
+        if (responseData.isEmpty()) {
+            qCWarning(colnod) << "empty response data when logging in";
+            emit downloadDataFinished(nullptr);
+            return;
+        }
+
+        token.fromJson(responseData);
         authToken = token.id();
+        if (authToken.isEmpty()) {
+            qCCritical(colnod) << "Token uuid is empty";
+            emit downloadDataFinished(nullptr);
+            return;
+        }
 
         auto data = std::make_shared<Data>();
 
diff --git a/src/colnod/data.h b/src/colnod/data.h
index bfc1eef..868bc03 100644
--- a/src/colnod/data.h
+++ b/src/colnod/data.h
@@ -43,12 +43,11 @@ struct PreparedData
 {
 public:
     PreparedData() = default;
-    PreparedData(std::shared_ptr<Data> database, std::shared_ptr<Data> colnod)
+    PreparedData(const std::shared_ptr<Data> &database, const std::shared_ptr<Data> &colnod)
         :databaseData(std::move(database)), colnodData(std::move(colnod))
     {
     }
 
-
     // TODO: make unique_ptr ( neeed because of ColnodAPI )
     std::shared_ptr<Data> databaseData;
     std::shared_ptr<Data> colnodData;