How to install rasa 2.x without using anaconda commands? I've created virtual environment having python 3.7.5 using pycharm

I'm trying to install rasa 2.1.2 without using any conda commands.

So far I've created virtual environment having python 3.7.5 using pycharm interpret settings. Installed other requirements like ujson, tensorflow.

Now, I'm trying to use this command:

pip install rasa==2.1.2

But getting error saying:

ERROR: Could not find a version that satisfies the requirement rasa==2.1.2(from versions:none)

ERROR: No matching distribution found for rasa==2.1.2