Sanic logger info doesn't show in gunicorn errorlog

from sanic.log import logger
logger.info(‘request data’)

gunicorn_config.py
loglevel = ‘info’
errorlog = ‘/var/log/file.txt’

gunicorn -c gunicorn_config.py manage:app
after I start the app, there is no any log message in /var/log/file.txt

is there any thing wrong?

thanks