Strapi referencing old host

Hi all! Im a long way with my Strapi & Dokku adventure and wanted to do the final step of putting my Strapi install on my live domain.

I did that but now when I load the admin url Strapi Admin I have errors in the chrome console like GET net::ERR_CERT_COMMON_NAME_INVALID where it’s trying to GET from the old domain host, you see? is my old host. I’ve changed my MY_HEROKU_URL var to reflect the new host: MY_HEROKU_URL: so thats not it.
And my config/env/production/server.js file is as follows:

module.exports = ({ env }) => ({
  url: env('MY_HEROKU_URL'),

I’ve restarted the dokku app with dokku ps:restart dutchenergy-strapi hoping that would fix it but it does not.

So what am I missing here?