@Anonymous Welcome to Microsoft Q&A forum! I understand that you want to change/rename the Azure IoT Hub host URL to custom name.
As mentioned on the other thread here currently there is no possibility to re-name the IoT Hub hostname URL. However, you can migrate/clone an Azure IoT hub to another region by exporting/using existing template. Using this template, you can create a new IoT Hub with the required name. Please see How to clone an Azure IoT hub to another region for more details and things to consider before cloning.
Good news is that our team is planned to add support for this feature soon and there is no exact ETA. I suggest you, kindly provide your feedback on the UserVoice entry: Add the custom domain name support for IOTHub Endpoint and follow Azure Updates for more updates.
Hope this helps. Do let us know if you have any further queries.
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