I do see your domain listed for new certs issued by Let’s Encrypt. For your site, Cloudflare is issuing its own certificate through DigiCert.
My guess is your host has renewed the certificate for your site on your server. This is “a good thing” since it’s important to have a valid certificate on your server. Have you asked your host about this?
For the FTP site, that’s going direct to a server that has a certificate installed for a different domain. Regular FTP doesn’t care about certs, so this shouldn’t affect you.