Django improperly loading while restarting it

Question

I have a website that is in VPS hosting. I was supposed to restart it with the following code

source .venv/bin/activate
uwsgi --ini agros.ini

But I am receiving the following error

django.db.utils.OperationalError: (2006, 'MySQL server has gone away')

here is the database configuration in the settings.py

DATABASES = {
'default': {
    'ENGINE': 'django.db.backends.mysql',
    'CONN_MAX_AGE': 3600,
    'NAME': 'agros_new',
    'USER': 'root',
    'PASSWORD': 'password',
    'HOST': 'localhost',
    'PORT': 3309,
 }
}

this website uses Django version = 1.9 and the operating system is the Centos OS