You could do this in a CustomAction. You’d invoke this action at some point in your dialogue and put in the following in the “run” method of the action class:
class SampleAction(Action):
def name(self):
return ‘SampleAction’
def run(self, dispatcher, tracker, domain):
####some code or no code here
return[SlotSet("Slot_to_be_reset_name", None")]
This is one way to do this.