Redirect NGINX HTTPS domain to new HTTPS domain

After spending hours using duckduckgo, this was the best answer I arrived at and it's still not working to redirect a currently HTTPS domain to a new HTTPS domain.

server {
    listen 80;
    listen 443 ssl;
    server_name www.olddomain.com olddomain.com;

    rewrite 301 https://newdomain.com$request_uri;
}

Browser gives Insecure Connection error.

I have also tried things like

server {
    listen 443 ssl;

    server_name olddomain.com;
    ssl on;
    ssl_certificate /etc/ssl/certs/OLD.crt;
    ssl_certificate_key /etc/ssl/private/OLD.key;

    #enables all versions of TLS, but not SSLv2 or 3 which are weak and now deprecated.
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;

    ssl_ciphers "ALLLLLLTTHHISSSS";
    ssl_prefer_server_ciphers on;


    rewrite 301 https://newdomain.com$request_uri;
}

Although this option stops giving an error the rewrite is not working and it goes to a "Welcome to NGINX Page."