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

Hello,
I have an OAK-D-S2 device and everything was working properly using this bunch of code:

from depthai_sdk import OakCamera, ArgsParser

import argparse

import depthai as dai

def a(packet):

for det in packet.detections:

spatials = det.img_detection.spatialCoordinates

print(spatials.x, spatials.y, spatials.z)

# parse arguments

parser = argparse.ArgumentParser()

parser.add_argument("-conf", "--config", help="Trained YOLO json config path", default='model/yolo.json', type=str)

args = ArgsParser.parseArgs(parser)

with OakCamera(args=args) as oak:

stereo = oak.create_stereo(fps=8)

color = oak.create_camera('color', fps=8)

nn = oak.create_nn(args['config'], color, nn_type='yolo', spatial=stereo)

oak.visualize(nn, fps=True, scale=2/3)

oak.callback(nn.out.passthrough, a)

oak.start(blocking=True)

Today, it gave me this error message: **AttributeError: 'NoneType' object has no attribute 'fromopenvino'***
I checked the camera using DepthAI_SDK, and it worked properly.

The code reaches to camera then it is opened and closed instantaneously after opening.

Any help, please?