Static files don't serve with Nginx

Hi, I am trying to deploy my website on server ubuntu 22.04 from digitalocean.I followed all the instructions to configure django with postgresql, gunicorn and nginx on digitalocean blog. Finally when I open domain on web browser it is fine,but it doesn’t serve the static files. Here is my relevant sections of code

settings.py file

DEBUG = False
STATIC_URL = 'static/'
STATIC_ROOT = os.path.join(BASE_DIR, 'static/')

PS: I have done with the collectstatic.

nginx file …

server {
    server_name example.com www.example.com 123.123.123.123;

    location = /favicon.ico { access_log off; log_not_found off; }
    location /static/ {
        alias /home/user/example.com/static/;

    }

    location / {
        include proxy_params;
        proxy_pass http://unix:/run/gunicorn.sock;
    }

Any idea to solve the problem. Thanks in advance