diff --git a/~dev_rating/application/classes/Controller/Api/V0/Student.php b/~dev_rating/application/classes/Controller/Api/V0/Student.php
index 343c25d5bae68bf16c397bec70032ac4cea42b6c..2ed58f3cfc8a3c27625f68883d7dbd0e73633118 100644
--- a/~dev_rating/application/classes/Controller/Api/V0/Student.php
+++ b/~dev_rating/application/classes/Controller/Api/V0/Student.php
@@ -71,10 +71,11 @@ class Controller_Api_V0_Student extends Controller_Handler_Api {
 
         if (!isset($recordBookData->planID)) {
             if (isset($recordBookData->planExternalID)) {
-                $recordBookData->planID = Model_Plan::withExternalID($recordBookData->planExternalID)->ID;
-                if ($recordBookData->planID == -1) {
+                $studyPlan = Model_Plan::withExternalID($recordBookData->planExternalID);
+                if (is_null($studyPlan)) {
                     throw new InvalidArgumentException('RecordBook: plan not found');
                 }
+                $recordBookData->planID = $studyPlan->ID;
             } else {
                 throw new InvalidArgumentException('RecordBook: no plan ids');
             }
@@ -188,7 +189,8 @@ class Controller_Api_V0_Student extends Controller_Handler_Api {
         }
 
         if (!isset($studentData->id) || ($studentData->id == -1)) {
-            $foundList = Model_Students::searchStudentsByName([$studentData->firstName, $studentData->secondName, $studentData->lastName], $facultyID);
+            $foundList = Model_Students::searchStudentsByName([$studentData->firstName,
+                $studentData->secondName, $studentData->lastName], $facultyID);
             $foundSet = [];
             foreach ($foundList as $item) {
                 if (!in_array($item['ID'], $foundSet)) {
diff --git a/~dev_rating/application/classes/Controller/Api/V0/StudyPlan.php b/~dev_rating/application/classes/Controller/Api/V0/StudyPlan.php
index 7cf5899b02022904a5f2e9aaaf0aa4767adb8281..9973ceee903b591bd0066f6d4bbbc055b78254da 100644
--- a/~dev_rating/application/classes/Controller/Api/V0/StudyPlan.php
+++ b/~dev_rating/application/classes/Controller/Api/V0/StudyPlan.php
@@ -83,7 +83,7 @@ class Controller_Api_V0_StudyPlan extends Controller_Handler_Api {
     private function processStudyPlan($studyPlanData, $year, $semesterID, $facultyID) {
         if (!isset($studyPlanData->id) && isset($studyPlanData->externalID)) {
             $studyPlan = Model_Plan::withExternalID($studyPlanData->externalID);
-            if (!isset($studyPlan)) {
+            if (!is_null($studyPlan)) {
                 $studyPlan = Model_Plan::make()
                     ->externalID($studyPlanData->externalID)
                     ->year($year)