Route 53 domain nameserver update stuck IN_PROGRESS 24+ hours, DuplicateRequest error blocking all changes

I only have Basic support so cannot open a Technical case.

Even if you're on a Basic Support plan (which would preclude you from raising a support call most of the time) you can still do so under Account and Billing -> Service: Domains -> Category: Registration Issue

https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/domain-contact-support.html

Even though your issue isn't a registration issue, it's still worth a try.

I understand you're experiencing a frustrating situation with your nameserver update being stuck in progress. However, I'm not able to directly cancel or clear specific operations, as I don't have access to AWS account management systems or the ability to modify operation states.

Based on the information available, the DuplicateRequest error occurs when a request is already in progress for the domain, which prevents new nameserver update requests from being submitted while the existing operation is still active.

For situations like this where an operation appears to be stuck and you're unable to manage your domain, you'll need direct assistance from AWS Support. While you mentioned having Basic support, I'd recommend:

1. Checking if you can upgrade to Developer or Business support temporarily to access technical support for this issue
2. Reaching out through the AWS Support Center to see what options are available for account and billing inquiries, which may be accessible even with Basic support
3. Using the AWS Forums or AWS re:Post community, where AWS support engineers sometimes monitor and respond to critical issues

Unfortunately, nameserver updates can sometimes take time to process, and when they encounter issues, they typically require AWS Support intervention to resolve, especially when blocking subsequent operations. This type of stuck operation scenario generally needs manual intervention from AWS engineers who have access to the domain registration systems.

I apologize that I cannot directly resolve this for you, but AWS Support will be your best path to getting this operation cleared and regaining control of your domain management.
Sources
UpdateDomainNameservers - Amazon Route 53