How are you doing? I heard from my friend that you are very familiar with suitecommerce. I am doing Secure Domain. I have tried to do Automatic certificate but it said that "Your DNS record is configured incorrectly." I also tried to do Manual Certificate, and I downloaded CSR generated by Netsuite. I am not sure how to upload CSR to CA.

My advice is to use automatic certificates whenever possible, as it will save you and your customer a lot of headache down the line. If you are sure you have set it up correctly, my suggestion is to wait a couple of hours. DNS propagation can take a while, and during that time, the application may say it is not configured correctly.