@Prasadjayasingh Is the device already registetred in DEP or are you manually adding it to DEP?
If you are manually adding the device what you are seeing is normal behaviour,
The 30-day provisional period means that users can remove device management during the first 30 days of management. During this provisional period, a banner appears on the device notifying them of the device management state and that they can leave remote management from the Settings menu. After 30 days, the provisional management will end, and users will no longer be able to remove remote management from the device.
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