Pyupdater client.update_check(APP_NAME,APP_VERSION) are always return none

Question

from pyupdater.client import Client,AppUpdate, LibUpdate
import logging
from client_config import ClientConfig 

logging.basicConfig(level=logging.DEBUG)
APP_NAME = 'PyUpdater App'
APP_VERSION = '1.1.0'

ASSET_NAME = 'PyUpdater App'
ASSET_VERSION = '1.2.0'


def progress(data):
    print('Time remaining'.format(data['time']))

def log_progress(data):
    log.debug('Total file size %s', data['total'])


# Or you can add them later.
client = Client(ClientConfig(),refresh=True,headers={'basic_auth': 
'wpN1q1X5wOuID21CFzjgdnNVY7qIOlipZeQACb3jeqc'})
#client.add_progress_hook(log_progress)
#client.add_progress_hook(progress)
client.platform = "win"
app_update = client.update_check(APP_NAME,APP_VERSION)
if app_update is not None:
    app_update.download()
else:
    print("Version 1")
#if app_update.is_downloaded():
    #app_update.extract()

#app_update.update_folder

Above code have some issue always gives error

DEBUG:pyupdater.client:Setting up directories...
DEBUG:dsdev_utils.helpers:Version str: 1.1.0
DEBUG:pyupdater.client:No update manifest found
Version 1

What is the reason?