no face detected err

app.py

@@ -50,7 +50,7 @@ def main_pipeline(image):
     faces = face_cascade.detectMultiScale(gray_img, 1.1, 4)
     
     if len(faces) == 0:
-        return "NO FACE DETECTED"
+        return original_image , "NO FACE DETECTED", "NO FACE DETECTED"
 
     x, y, w, h =  faces[0]
     #cv2.rectangle(image, (x, y), (x+w, y+h), (255, 0, 0), 2)