Verify the domain’s A record and check that it points at the panel server. After a DNS change, give it time to propagate.
The installer checks the record before ordering a certificate. If the DNS check passed but no certificate was issued, check port 80, which is needed for HTTP-01 validation, and look for a conflict with another service.
Once the cause is fixed, run the installer again. It keeps the configuration and data, so nothing needs to be uninstalled. Do not retry blindly: the certificate authority rate-limits failed orders.
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