Check CAA record of the domain.
Certificate Authority Authorization (CAA) record is a less common DNS record type. It is primarily used for locking down on a list of Certificate Authorities (CA), except for which nobody can issue an SSL/TLS certificate for your domain.
In the absence of this, any public certificate authority is allowed to issue certificates for any domain. That said, having a CAA record doesn't tie you up with a specific certificate authority, and you can add multiple CAs for this purpose.
Domsignal DNS CAA lookup tool can help you identify the CAs configured to issue a standard or wildcard certificate for the subject domain.
This configuration is mainly done to prevent certificate misuse or unintended issue to anyone other than the actual website owner.
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