Removing the let's encrypt certificate issued for the panel

[imeuropa]

Hey, some years ago I set VestaCP up on my server with the hostname server1.domain.tld for the panel. After installing I enabled let's encrypt SSL for the panel and it worked perfectly. But now I don't have access to that domain anymore, I've changed the FQDN hostname on the server and at the host but when I go to the panel it sais "Not Secure" because it's still trying to use the old let's encrypt certificate for the panel on the old hostname. Is there any way to disable or remove the certificate and then re-issue it for the correct hostname?
Thanks in advance.