dispatcher.utter_message in a slot validation action does not display in a conversation

[ancalita]

Problem description:
Using a dispatcher.utter_message(text=..) inside a custom validation method in a custom action extending ValidationAction does not get displayed to the user in a rasa shell conversation, although the debug log shows that the BotUttered event was added to the tracker.

Example of custom action code:

class TravelSlotValidation(ValidationAction):
    @staticmethod
    def location_db() -> List[Text]:
        """Database of supported locations."""
        return ["copenhagen", "vancouver", "london", "paris", "lima",
                "san sebastian", "aspen", "queenstown", "new york", "milan"]

    def validate_location(
        self,
        slot_value: Any,
        dispatcher: CollectingDispatcher,
        tracker: Tracker,
        domain: DomainDict,
    ) -> Dict[Text, Any]:
        if slot_value.lower() in self.location_db():
            return {"location": slot_value}
        else:
            dispatcher.utter_message(text='Your city is not yet supported. Please try again')
            return {"location": None}

Definition of Done

• bot message is shown to user in rasa shell.

[stale]

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[stale]

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[rajpar29]

Do we have any updates on this?
@ancalita did you find a fix or workaround?

[ancalita]

Fix released in rasa-oss version 3.2.5.

[tedd0n]

Still having the same problem. Rasa version 3.6.13