The Unable to process your request error most commonly occurs if you're in the process of transferring your domain. While a transfer is pending, you can't change your name servers. As soon as your transfer has completed, you can manage your name servers with your new registrar.

Another reason that you might get this error message, is due to an error in the name server names. Contact your hosting provider and re-confirm the name servers that you were given

The last and least common reason for this error is due to the name servers not being registered. Once you've confirmed the name servers, you may need to contact customer support to have your name servers registered. Before you contact customer support be ready to provide the IP address assigned to each name server you need to register.