I have followed this guide to setup my LetsEncrypt SSL certificate on my Digital Ocean / Serverpilot / WordPress setup https://www.youtube.com/watch?v=d8cAz1jiJ1s and have successfully generated the certificate.
You probably need to go into your WP admin and change the settings there to use https rather than http.
Also the config file for your https is slightly incorrect ( it’s sending php rather than interpreting it if you go to https://hoy.co.uk/index.php ) and it’s not redirecting to index.php … I’d start by comparing the config for http and config for https and see what you are missing ( or paste the config file in pastebin.com for us, and provide a link )
hmm, working for me - https://www.hoy.co.uk/wp-login.php that wouldn’t usually be helped by clearing cache or restarting your browser - but may be worth a go.