Why an SSL order can be rejected? There are several possible ways for the cert to get into this status.

1. The first way is to reject the order via the validation email. This option is to be selected if you actually did not request the certificate or you changed your mind on getting it.

Important! If you select to Reject the approval email during the reissue, this will result in the whole order cancellation, no matter whether the certificate is still refundable or not. It will not be possible to pull up the rejected order back to the "Active" status.

Below you can find the examples of how the Reject option looks like in the verification emails from Comodo (now Sectigo CA).

By following the link in Comodo (Sectigo) validation email you will be forwarded to the rejection page:

You will be offered to supply additional information:

We would like to draw your attention to our Refund Grace periods terms: 15 days after the certificate factual issuance. So, you will not lose money if you reject a recently purchased certificate.

Please contact our Support Team if any assistance is required.

2. The second situation is when your certificate is rejected by the Certification Authority.

All Certification Authorities can reject orders for a ‘banned’ country (according to the US Export laws): the information in the CSR contains the banned country code, the company is registered or located in a banned country or even if the IP address of the approver indicates such a country. Sectigo CA provides an SSL-banned countries list on its website. You can also find it below:

The Republic of Belarus (BY)
Cuba (CU)
Iran (IR)
North Korea (KP)
The Russian Federation (RU)
Syria (SY)
Venezuela (VE, GOV.VE)

Comodo (Sectigo) orders can also be rejected due to Brand Name usage. For instance, if you activate the SSL for windowsexample.com domain, most probably the cert will be rejected by the Certification Authority system automatically.

Rejected Comodo (Sectigo) orders are not refunded automatically. If you are not receiving your certificate after the Brand Validation step, please contact our support to check the order and have a refund issued in case your order was rejected. As an alternative, it is possible to change the Comodo (Sectigo) certificate back to New status, and you will be able to activate it for another domain.

3. The order can also be rejected in case with "Brand validation" status, please refer to this article.
   

Note: To check the order state and take action to expedite your Certificate issue, use the convenient SSL Validation Tool.