USB Webcam Not Working on Jetson Nano for OpenCV/TensorFlow Object Detection

[ WARN:0] global /tmp/pip-req-build-1234abcd/opencv/modules/videoio/src/cap_v4l.cpp (890) open VIDEOIO(V4L2:/dev/video0): can't open camera by index

import cv2
import tensorflow as tf

# Load the pre-trained object detection model
model = tf.saved_model.load('ssd_mobilenet_v2/saved_model')

# Open the USB webcam
cap = cv2.VideoCapture(0)

while cap.isOpened():
    ret, frame = cap.read()
    if not ret:
        print("Failed to capture image")
        break
    
    # Preprocess the frame for the model
    input_tensor = tf.convert_to_tensor(frame)
    input_tensor = input_tensor[tf.newaxis, ...]

    # Perform object detection
    detections = model(input_tensor)

    # Display the frame
    cv2.imshow('Frame', frame)
    
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

cap.release()
cv2.destroyAllWindows()