Why would a Case ID be completely missing on my AWS account?

It is recommended to reach out to the AWS Premium Support & provide them with the Case-ID. It could be that the Case-ID is wrong or different from the one being searched. Reach out to the Premium support and they can help navigate the same with the use of internal tools since it is difficult to check the same without having the Case-ID and other necessary details. Link- https://aws.amazon.com/contact-us/