Categorical Slot is returning None. How do I solve it?

Rasa Open Source
1

Hi! I am new to Rasa. So, I am having a hard time in using categorical slots for my basic example bot. I have provided my stories.md, action function and domain.yml below.

stories.md

## fallback
- utter_nodata


## Story 1
* greet
    - utter_greeting
* inform{"subcategory": "laser"}
    - slot{"subcategory":"laser"}
    - utter_feature
* inform{"feature": "Google Cloud"}
    - slot{"feature":"Google Cloud"}
    - utter_price
* inform{"price": "150"}
    - action_get_printer

## Story 2
* greet
    - utter_greeting
* inform{"subcategory": "inkjet"}
    - slot{"subcategory":"inkjet"}
    - utter_feature
* inform{"feature": "Air Print"}
    - slot{"feature":"Air Print"}
    - utter_price
* inform{"price": "200"}
    - action_get_printer

## Story 3
* greet
    - utter_greeting
* inform{"subcategory": "I don't know"}
    - slot{"subcategory":"I don't know"}
    - utter_feature
* inform{"feature": "Amazon Dash"}
    - slot{"feature":"Amazon Dash"}
    - utter_price
* inform{"price": "100"}
    - action_get_printer

domain.yml

intents:
- greet
- inform

entities:
- subcategory 
- feature
- price

slots:
   subcategory:
            type: categorical
            values:
              - Laser
              - Inkjet
              - I don't know
   feature:
            type: text
   price:
            type: float

actions:
- utter_greeting
- utter_feature
- utter_price
- utter_nodata
- action_get_printer

templates:
  
  utter_greeting:
  - text: "Hello. Which type of printer do you need?"
  
  utter_feature:
  - text: "Any specific feature that you would like in your printer?"
  
  utter_price:
  - text: "What is the upper cap of your budget?"
  
  utter_nodata:
  - text: "Sorry, we don't have that data"

action

class getPrinterInfo(Action):
	def name(self):
		return 'action_get_printer'

	def run(self, dispatcher, tracker, domain):
		sub_category = tracker.get_slot('subcategory')
		feature = tracker.get_slot('feature')
		price = tracker.get_slot('price')

		message = f'The {sub_category} with {feature} and cheaper than {price} is:'
		dispatcher.utter_message(message)

		return []
2

Hey @seldomcoder. First thing you should check is if your NLU model extracts the entity correctly. Can you confirm that?