@MyAzQuery If possible, it is advised that you place the resource guard in another subscription or another tenant to address such scenarios that can help you isolate better.
Would like to understand the policy requirement better- are you looking for a Deny assignment or something like an Azure Policy with Deny effect?
If you're wanting to deny using policy for azure subscription owner from disabling MUA. Then this is not possible as of today. Because there is a bit of pre-requisite work needed from our end (making MUA settings accessible by Azure Policy) in order to enable customers to write a deny policy for disabling MUA. This is on our roadmap, and we’ll be able to get back on more details around timelines.
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