diff --git a/src/main/java/com/seg83/childbank/gui/component/taskpanel/TaskPop.java b/src/main/java/com/seg83/childbank/gui/component/taskpanel/TaskPop.java
index 98d54df..1bdc8ec 100644
--- a/src/main/java/com/seg83/childbank/gui/component/taskpanel/TaskPop.java
+++ b/src/main/java/com/seg83/childbank/gui/component/taskpanel/TaskPop.java
@@ -100,6 +100,10 @@ private void onOK() {
 
         // id should be a number
         try {
+            if (id <= 0) {
+                JOptionPane.showMessageDialog(this, "Task No. should be a positive number", "Error", JOptionPane.ERROR_MESSAGE);
+                return;
+            }
             id = Long.parseLong(textField1.getText());
         } catch (NumberFormatException e) {
             JOptionPane.showMessageDialog(this, "Task No. should be a number", "Error", JOptionPane.ERROR_MESSAGE);
@@ -182,4 +186,4 @@ public void init() {
         return contentPane;
     }
 
-}
\ No newline at end of file
+}