How to end this conversation session when the bot ask user for one of them over three times and still not fill correct

I want to implement a function in my bot, for example, in WeatherForm(FormAction) , there are two required slots[“date_time”, “address”], How to end this conversation sessionwhen the bot ask user for one of them over three times and still not fill correct

class WeatherForm(FormAction):

def name(self) -> Text:
    """Unique identifier of the form"""

    return "weather_form"

@staticmethod
def required_slots(tracker: Tracker) -> List[Text]:
    """A list of required slots that the form has to fill"""

    return ["date_time", "address"]

def submit(
        self,
        dispatcher: CollectingDispatcher,
        tracker: Tracker,
        domain: Dict[Text, Any],
) -> List[Dict]:
    """Define what the form has to do
        after all required slots are filled"""
    address = tracker.get_slot('address')
    date_time = tracker.get_slot('date_time')

    return []