Redirecting Traffic from www.domain.com to domain.com

I’ve decided to use the one-click Ghost install on digitalocean, and I like how easy it has made the process. However, I am having an issue with my site. I want to redirect the www.domain.com to domain.com, but my config doesn’t seem to work.

I have Letsencrypt certs for my domain which is arsalan.io, and it works fine. It gives a cert error if you try www.arsalan.io, so since I don’t want people browsing to www, I’d rather just have it forwarded to arsalan.io. I’ve setup www as a CNAME that points to the main domain.

My NGINX config is as follows (/etc/nginx/sites-available/arsalan.io.conf):

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

    server_name arsalan.io;
    root /var/www/ghost/system/nginx-root;

    location / {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Host $http_host;
        proxy_pass http://127.0.0.1:2368;

    }

    location ~ /.well-known {
        allow all;
    }

    client_max_body_size 50m;
}

I’ve tried modifying it so it looks like the following but it doesn’t redirect:

server_name arsalan.io www.arsalan.io;
redirect 301 https://arsalan.io$request_uri;

I haven’t modified arsalan.io-ssl.conf