Thank you for posting this in Microsoft Q&A.
As I understand you are getting error while trying to access the device blade in your Entra ID portal.
You want to know ways to find the administrators in your Entra ID.
If you don’t know who are the admins then you can follow below steps to know who are the admin in your tenant. There is a PowerShell way to find global admin in your Azure AD. However, to use PowerShell as well you will have to authenticate yourself first.
• Open Windows PowerShell as administrator.
• Run command “Install-Module azuread”
• Once installed you can run command “Connect-AzureAD” and enter your credentials once it asks for.
• Once you login, you can run command “Get-AzureADDirectoryRole”.
• From the output you can copy the object ID of Global administrator
• Run command “Get-AzureADDirectoryRoleMember -ObjectId "Paste the object ID of global admin that was copied earlier"
• You will get the list of users with global admin role assigned.
You can contact them directly and ask them to perform the steps to get the device enabled again.
Let me know if you have any further questions.
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