I am very new python. And I am struggling to auto refresh markers using dash leaflet. Code refreshes popup of marker, gets updated data from data base in interval time as expected. But color of markers are not refreshing. Only hard refresh of the page helps. I also have tried to refresh whole page with no success, same behaviour

How to fix the code to auto refresh markers on page?

import json
import dash
import dash_leaflet as dl
from dash import html, dcc
from dash.dependencies import Input, Output
import psycopg2
from database import DATABASE_CONFIG
from datetime import datetime

app = dash.Dash(__name__)

query = """
    select
        name, latitude, longitude,
        case
            when ss <= 3600 then 'green'
            when ss > 3600 and ss <= 86400 then 'orange'
            else 'red'
        end as type
    from (
        select
            city.name, city.latitude, city.longitude, EXTRACT(EPOCH FROM (now() - max(dat."updateTime"))) as ss
        from 
            public."microController" mic
            left join public."mainData" dat on mic."controllerID" = dat."controllerID"
            join public."dictCity" city on mic."cityId" = city.id
        where
            mic."isDeleted" = false
        group by mic."cityId", city.name, city.latitude, city.longitude
    ) t
"""

def get_city_data():
    try:
        conn = psycopg2.connect(**DATABASE_CONFIG)
        cur = conn.cursor()
        cur.execute(query)
        cities = cur.fetchall()
        cur.close()
        conn.close()
        return cities
    except Exception as e:
        return []

with open("countries.geojson", encoding='utf-8') as f:
    geojson_data = json.load(f)

country_feature = None
for feature in geojson_data['features']:
    if feature['properties'].get('ADMIN') == 'Kazakhstan':
        country_feature = feature
        break

if not country_feature:
    raise ValueError("Failed to find country in GeoJSON data")

app.layout = html.Div([
    dl.Map(
        id='map',
        style={'width': '100%', 'height': '100vh'},
        center=[48.0, 68.0],
        zoom=5,
        children=[
            dl.TileLayer(),
            dl.GeoJSON(id='geojson', data=country_feature),
            dl.LayerGroup(id='city-markers')
        ]
    ),
    dcc.Interval(
        id='interval-component',
        interval=5 * 1000,
        n_intervals=0
    )
])

@app.callback(
    Output('city-markers', 'children'),
    Input('interval-component', 'n_intervals')
)
def update_map(n_intervals):
    city_data = get_city_data()

    if not city_data:
        return []
    
    current_time = datetime.now().strftime("%H:%M:%S")
    
    city_circles = [
        dl.CircleMarker(
            center=[city[1], city[2]],
            radius=10,
            color='black',
            fillColor=city[3],
            fillOpacity=0.6,
            stroke=True,
            children=[dl.Popup(f"{city[0]} - updated at {current_time}")]
        )
        for city in city_data
    ]

    return city_circles

if __name__ == '__main__':
    app.

run_server(debug=True)