@Dikesh Shrestha, Thanks for posting in Q&A.
Based on my research, if you already renamed the device but don't see its new name, the device might need to check in to Intune. Also, if you have an enrollment profile (iOS) that uses a Device Name Template, the device will be renamed but will revert to using the template upon the next sync with Intune.
https://learn.microsoft.com/en-us/mem/intune-service/remote-actions/device-rename#rename-a-device
Also, please check the iOS enrollment profile and OS version in the supported list.
https://learn.microsoft.com/en-us/mem/intune-service/remote-actions/device-rename
And try to manually sync it with Intune on device side and reboot device to see if it can work.
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