Error when running deep learning object detection model with arcgis.learn

[AnthonyFong]

Hi, I am exploring the deep learning object detection model with ArcGIS Pro 2.4. While I was trying to following the online tutorial (Use Deep Learning to Assess Palm Tree Health | Learn ArcGIS) for the step of "Train a deep learning model" with the Jupiter Notebook , I encountered the following error:

The error states the module requires fastai, PyTorch and torchvision as its dependencies. I have checked and run the command to install those plugins again, but the command prompt showed all these plugins have been successfully installed. I even tried on another computer, but same error shown. Grateful if anyone could help on this.