Comodo (now Sectigo CA) does not require any other verification procedures for PositiveSSL and EssentialSSL Certificates other than validation of your domain ownership. It can be done by either receiving the validation email or uploading a certain text file into a particular directory of your
website (/.well-known/pki-validation/) or adding a certain CNAME record to the DNS zone of your domain.
If you have activated the certificate with domain.com or www.domain.com
indicated as FQDN in your CSR code, please make sure that the file is available
via http://domain.com/.well-known/pki-validation/file.txt . In this
case, www.domain.com is considered to be under your control as well.
Content of the file shouldn't be changed in any way, as Comodo (Sectigo) validation system is case sensitive.
It means that there should be no delays in issuance of PositiveSSL or EssentialSSL. If your certificate is not delivered in 2 hours since you approved the approver email, please contact our SSL Support Team for assistance.
You can read more details about verifying domain ownership for these certificates here.
Note: To check the progress status and take action to expedite your Certificate issue, use the convenient SSL Validation Tool.