Nginx in docker does not see the certificate files

General
,
1

Expected behavior

Site to be served via https

Actual behavior

Site does not get served at all.
Docker compose logs for nginx container return:

nginx: [emerg] cannot load certificate "/etc/nginx/certs/fullchain1.pem": BIO_new_file() failed (SSL: error:80000002:system library::No such file or directory:calling fopen(/etc/nginx/certs/fullchain1.pem, r) error:10000080:BIO routines::no such file)

Additional Information

The nginx configuration is as follows:

events {
    
}

http {
    server {
    listen 80;
    listen [::]:80;

    server_name my-reducted-domain.com www.my-reducted-domain.com;
    server_tokens off;

        location / {
            proxy_pass http://flask:56733;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            # Additional proxy settings if needed...
        }
    }
    server {
    listen 443 ssl;
    server_name my-reducted-domain.com;
        ssl_certificate /etc/nginx/certs/fullchain1.pem;
        ssl_certificate_key /etc/nginx/certs/privkey1.pem;
    client_max_body_size 20M;
    index index.html;
        location / {
                proxy_pass http://my-reducted-domain.com;
        }
    }
}

The docker-compose.yml relelvant service is:

  nginx:
    image: nginx:alpine
    container_name: spun-flask-nginx
    restart: unless-stopped
    ports:
      - 80:80
    volumes:
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
      - ./certs:/etc/nginx/certs  
    networks:
      - flask

The directory certs has inside:

myuser@spun-test-8-nginx-docker-compose:/var/lib/myproject$ ls -l certs
total 24
-rw-r--r-- 1 myuser docker   66 Nov 23 11:54 README
-rw-r--r-- 1 myuser docker 1497 Nov 23 12:40 cert1.pem
-rw-r--r-- 1 myuser docker 3749 Nov 23 12:40 chain1.pem
-rw-r--r-- 1 myuser docker 5246 Nov 23 12:39 fullchain1.pem
-rw------- 1 myuser docker  241 Nov 23 12:40 privkey1.pem

When I do an ls from inside the nginx container I see the files being there:

myuser@spun-test-8-nginx-docker-compose:/var/lib/myproject$ docker-compose run --rm nginx ls -l /etc/nginx/certs/
total 24
-rw-r--r--    1 1001     997             66 Nov 23 11:54 README
-rw-r--r--    1 1001     997           1497 Nov 23 12:40 cert1.pem
-rw-r--r--    1 1001     997           3749 Nov 23 12:40 chain1.pem
-rw-r--r--    1 1001     997           5246 Nov 23 12:39 fullchain1.pem
-rw-------    1 1001     997            241 Nov 23 12:40 privkey1.pem

As a test (only a test) I tried changing ownership or permissions of the files, and always get the same error:

cannot load certificate "/etc/nginx/certs/fullchain1.pem"

Any ideas what else to try?