@Junior , Thanks for posting in our Q&A. For the "Full disk access" setting, I notice it only apply to user approved device enrollment, Automated device enrollment. Please check if our device meets this.
If the above is met, but the setting still not applied. I think this issue needs to do log analysis. With Q&A limitation, we suggest to open case to handle such issue. Here is a link with the steps to open case for your reference:
Thanks for your understanding.
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