Bucket with no data

I created a python SDK to fetch the data from the bucket.
However I cannot fish current data from the bucket.

This is my code:

my_device = TagoAPI(sensor.device_token)

    filter = {

        "qty": 50,

        "end_date": request.now.strftime("%Y-%m-%d %H:%M:%S"),

        "start_date": ultimo_dado.strftime("%Y-%m-%d %H:%M:%S"), #"2021-09-19 00:00:00", ultimo_dado

        "details": "true",

        # "variable": "variable[]=command&variable[]=temperatura&variable[]=humidade"

        

    }
resultados.append(my_device.data(filter))

    print(resultados)

Hi,

Can you explane more, i not understand your doubt.

Thanks, Rafael Teles.