@Lee
Thank you for the quick response!
I reached out to our ASC team, and was told that if you're using RBAC roles you should be able to quickly find which subscription is missing permissions. However, if you have any custom roles/groups this can be considerably time consuming to figure out which subscription needs the permissions. Lastly, if you'd like our ASC team to take a closer look into your environment, they'd be able to figure out which permissions you need.
Additional Link:
Permissions in Azure Security Center
If you have any other questions or would like to be enabled for a free technical support request, please let me know.
Thank you for your time and patience throughout this issue.
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@JamesTran-MSFT attached is a copy of the error message.