Methods decorated with @start in flow get executed parallelly but ...... head on to description

It is said in officail documentation methods decorated with @start in flow get executed parallelly but i am trying using crewai chatgpt assistance. It is not working. unexpectedly, 1 in 20 execution it works. I am not able to figure out the reason.

Here is flow i have written :


class Realtime86Flow(Flow[Realtime86State]):

    """Real Time 86 Flow Implementation"""

    def __init__(self):
        """Initialize the flow with optional parameters"""
        super().__init__()

    @start()
    async def coordinator_task(self)->str:
        print("Inside Coordinator RealTime86 flow")
        crew = CoordinatorCrew().crew()
        tick = {"action": "publishing :REALTIME_86_TRIGGER"}
        await crew.kickoff_async(inputs={
            "topic": "realtime86.trigger",
            "message": tick
        })
        return "Coordinator Done"


    @start()
    async def inventory_sensor_task(self)->str:
        print("Inside Inventory RealTime86 flow")
        crew = InventorySensorCrew().crew()
        await crew.kickoff_async(inputs={
            "subscriber_topic": "realtime86.trigger",
            "publisher_topic": "low.stock.items",
            "failure_topic": "86.failures"
        })
        return "Inventory Sensor Done"

    @listen(and_(coordinator_task,inventory_sensor_task))
    def is_realtime86_activated(self,is_activated)->None:
        print(f"Outside @start : {"RealTime86 Activated"}")
        logger.info(f"Outside @start : {"RealTime86 Activated"}")
        # # Keep main thread alive if needed
        # while True:
        #     time.sleep(10)