Can't install previous PyTorch versions with Pycharm

Hi,

I want to use the torch 1.5.1 and torchvision 0.6.1. I accidentally downloaded the current latest version of pytorch but I run on a bug after some several runs related with the sampling from a categorical distribution.

For that reason, I wanted to downgrade to a version that the same code had worked perfectly in the past. I tried all of these commands but despite the fact that they were installed succesfully based on Pycharm’s terminal message, when I import them in the code I get this ModuleNotFoundError: No module named 'torch.

Does anyone know why is this happening?