diff --git a/backend/src/main/java/core/services/TaskService.java b/backend/src/main/java/core/services/TaskService.java
index 1b4bc14..292b442 100644
--- a/backend/src/main/java/core/services/TaskService.java
+++ b/backend/src/main/java/core/services/TaskService.java
@@ -90,7 +90,9 @@ public class TaskService {
     public void deleteTask(Task task) {
         task.getTaskgroup().getTasks().remove(task);
         taskgroupRepository.save(task.getTaskgroup());
-        taskSeriesService.deleteTaskSeriesItem(task);
+        if(task.getTaskSerieItem() != null) {
+            taskSeriesService.deleteTaskSeriesItem(task);
+        }
         taskRepository.delete(task);
 
     }