diff --git a/src/main/java/at/ionas999/solution/controller/FastWatchController.java b/src/main/java/at/ionas999/solution/controller/FastWatchController.java
index 57e2bc0..52869f3 100755
--- a/src/main/java/at/ionas999/solution/controller/FastWatchController.java
+++ b/src/main/java/at/ionas999/solution/controller/FastWatchController.java
@@ -71,12 +71,29 @@ public class FastWatchController {
         this.linHandMinutes.setEndY(Math.sin(minuteRadians) * length * 0.8);
     }
 
+    @FXML
     public void btnAdjustOnAction(ActionEvent actionEvent) {
-        int[] time = Arrays.stream(this.txtTime.getText().split(":"))
-                .mapToInt(Integer::parseInt)
-                .toArray();
-        DayOfWeek dayOfWeek = this.cmbDayOfWeek.getValue();
-        WatchTime.getInstance().setTime(time[0], time[1], dayOfWeek);
+        try {
+            int[] time = Arrays.stream(this.txtTime.getText().split(":"))
+                    .mapToInt(Integer::parseInt)
+                    .toArray();
+            if (time.length != 2 || time[0] < 0 || time[0] > 23 || time[1] < 0 || time[1] > 59) {
+                throw new NumberFormatException("Invalid time format");
+            }
+            DayOfWeek dayOfWeek = this.cmbDayOfWeek.getValue();
+            WatchTime.getInstance().setTime(time[0], time[1], dayOfWeek);
+        } catch (NumberFormatException e) {
+            ShowAlert("Invalid time format", "Please use a this format HH:MM");
+        }
+    }
+
+    private void ShowAlert(String header,String content)
+    {
+        Alert alert = new Alert(Alert.AlertType.ERROR);
+        alert.setTitle("Invalid Input");
+        alert.setHeaderText(header);
+        alert.setContentText(content);
+        alert.showAndWait();
     }
 
 }