Vk_api.exceptions.ApiError: [100] One of the parameters specified was missing or invalid: message is empty or invalid

import vk_api
from vk_api.bot_longpoll import VkBotLongPoll, VkBotEventType
import random
 
vk_session = vk_api.VkApi(token = 'Тут есть токен')
longpoll = VkBotLongPoll(vk_session, 205517442)
session_api = vk_session.get_api()
 
def sender(id, text):
    vk_session.method('messages.send', {'user_id' : id, 'message' : text, 'random_id' : 0})
 
def photo(id, url):
    session_api.messages.send(user_id = id, attachment = url, random_id = 0)
 
def chat_photo(id, url):
    session_api.messages.send(chat_id = id, attachment = url, random_id = 0)
 
 
def sticker(id, number):
    session_api.messages.send(user_id = id, sticker_id = number, random_id = random.randint(-1234567, +1234567))
 
def chat_sender(chat_id, text):
    vk_session.method('messages.send', {'chat_id' : chat_id, 'message' : text, 'random_id' : 0})
 
for event in longpoll.listen():
    if event.type == VkBotEventType.MESSAGE_NEW:
        id = event.object.message['from_id']
        msg = event.object.message['text'].lower()
 
#беседа
        if event.from_chat:
 
            chat_id = event.chat_id
 
            if msg == 'ку':
                chat_sender(chat_id, 'привет')
 
            if msg == 'ку':
                chat_photo(chat_id, 'photo-201201859_457239020')
 
        if event.from_chat:
            chat_id = event.chat_id
 
            if msg == '':
                chat_sender(chat_id, '')
 
            if msg == 'ку':
                chat_photo(chat_id, '')
 
#лс
        else:
 
            if msg == 'доброе утро':
                sender(id, 'Доброе!')
 
            if msg == 'доброе утро':
                photo(id, '')