Why the TensorRT mdoel doesn't show class names(model.names)?

[miladfa7]

I have converted the model to TensorRT format using this code

model.export(format='engine', half=True, imgsz=[544,960], batch=10, device=0)

but after exporting model, I want to see class names but it shows just None value as result.

tensorrt_path ="train4/weights/best.engine"
trt_model = YOLO(tensorrt_path)
print(trt_model.names)

Output:
None

Also when the tensorrt model used for inference, the model has not detected any object. results model was empty.
I mean.
results = trt_model.predict(frames, imgsz=[544,960], batch=10, device=0)