How to deal with the periodic "falling off" Celery?

Question

Django

Hello colleagues.
I use celery in conjunction with Django. Here is the service config:

[Unit]
Description=celery daemon
After=network.target

[Service]
User=reviews
Group=reviews
WorkingDirectory=/opt/xxx/web/
Environment="PATH=/opt/xxx/bin"
ExecStart=/opt/xxx/bin/celery worker -A AppReviews

[Install]
WantedBy=multi-user.target

CELERY_BROKER_URL = 'redis://:[email protected]/0'
CELERY_RESULT_BACKEND = 'redis://:[email protected]/1'
CELERY_TASK_SERIALIZER = 'json'
CELERY_ACCEPT_CONTENT = ['json']

The scheme is as follows: when an object is saved to the database, a signal is triggered and, under certain conditions, a task is created for Celery. It works, but periodically the tasks stop being created (I monitor through flower). After restarting the service, everything starts working.
Actually, how to diagnose it and how to fix it?
PS It works through redis, it is more alive than all the living.