diff --git a/lms/nladmin-system/src/main/java/org/nl/b_lms/sch/tasks/slitter/SendShaftToCacheTask.java b/lms/nladmin-system/src/main/java/org/nl/b_lms/sch/tasks/slitter/SendShaftToCacheTask.java
index 39763624f..ecf61e6df 100644
--- a/lms/nladmin-system/src/main/java/org/nl/b_lms/sch/tasks/slitter/SendShaftToCacheTask.java
+++ b/lms/nladmin-system/src/main/java/org/nl/b_lms/sch/tasks/slitter/SendShaftToCacheTask.java
@@ -182,7 +182,7 @@ public class SendShaftToCacheTask extends AbstractAcsTask {
     }
 
     @Override
-    public JSONObject immediateNotifyAcs(Object task_id) {
+    public JSONObject immediateNotifyAcs(String task_id) {
         try {
             Thread.sleep(1000);
         } catch (Exception ex) {