AttributeError: 'NoneType' object has no attribute 'landmark'

I am on windows, using jupyter notebook, Mediapipe:Holistic Solution, Python, tensorflow.

I am using a Holistic solution and trying to get the left hand, right hand and pose landmarks. I am giving my webcam feed as input.

When I run the code below, there are no errors and everything is good.

After this, I was trying to check if I got the landmarks by using results.left_hand_landmarks.landmark and length of the landmarks using len(results.left_hand_landmarks.landmark) I am getting this AttributeError: 'NoneType' object has no attribute 'landmark'

The funny part is the problem is only with left hand and right hand landmarks. I was able to get the Pose landmarks and its length. Please help.

    cap = cv2.VideoCapture(0)
# Set mediapipe model 
with mp_holistic.Holistic(min_detection_confidence=0.5, min_tracking_confidence=0.5) as holistic:
    while cap.isOpened():

        # Read feed
        ret, frame = cap.read()

        # Make detections
        image, results = mediapipe_detection(frame, holistic)
        print(results)
        
        # Draw landmarks
        draw_styled_landmarks(image, results)

        # Show to screen
        cv2.imshow('OpenCV Feed', image)

        # Break gracefully
        if cv2.waitKey(10)  0xFF == ord('q'):
            break
    cap.release()
    cv2.destroyAllWindows()