Index: frontend/src/components/SubjectCatalog/SubjectCatalog.tsx
===================================================================
--- frontend/src/components/SubjectCatalog/SubjectCatalog.tsx	(revision f53d0f20ff4ee537b3a2e61e63f1bc303f456ff2)
+++ frontend/src/components/SubjectCatalog/SubjectCatalog.tsx	(revision 3c113dcd816eb6af220634e019fb863d0db866ea)
@@ -56,5 +56,7 @@
 
 	const openSubjectDetails = (subject: Subject) => {
-		setSelectedSubject(subjectData[subject.id - 1]);
+		setSelectedSubject(
+			subjectData.find((item) => item.id == subject.id) ?? null
+		);
 		setShowModal(true);
 	};