diff --git a/lang/en/local_treestudyplan.php b/lang/en/local_treestudyplan.php
index 9e873db..91ab505 100644
--- a/lang/en/local_treestudyplan.php
+++ b/lang/en/local_treestudyplan.php
@@ -96,7 +96,7 @@ $string['studyplan_context'] = 'Context';
 $string['studyplan_shortname'] = 'Short name';
 $string['studyplan_shortname_ph'] = '';
 $string['studyplan_idnumber'] = 'ID Number';
-$string['studyplan_shortname_ph'] = '';
+$string['studyplan_idnumber_ph'] = '';
 $string['studyplan_description'] = 'Description';
 $string['studyplan_description_ph'] = '';
 $string['studyplan_slots'] = 'Number of periods in plan';
diff --git a/lang/nl/local_treestudyplan.php b/lang/nl/local_treestudyplan.php
index 9edb760..04cd2ed 100644
--- a/lang/nl/local_treestudyplan.php
+++ b/lang/nl/local_treestudyplan.php
@@ -98,7 +98,7 @@ $string['studyplan_context'] = 'Context';
 $string['studyplan_shortname'] = 'Korte naam';
 $string['studyplan_shortname_ph'] = '';
 $string['studyplan_idnumber'] = 'Opleidings-ID';
-$string['studyplan_shortname_ph'] = '';
+$string['studyplan_idnumber_ph'] = '';
 $string['studyplan_description'] = 'Beschrijving';
 $string['studyplan_description_ph'] = '';
 $string['studyplan_slots'] = 'Aantal periodes in studieplan';