Hi @Pallab Chakraborty ,
In order to assign the role, your user account need to have the Owner or User Access Administrator role assigned at the subscription level. Please make sure that you have either the Owner or User Access Administrator role assigned to yourself at the subscription level.
You also need to ensure that you have the right number of Azure AD Premium P2 licenses assigned to use PIM. https://learn.microsoft.com/en-us/azure/active-directory/privileged-identity-management/subscription-requirements
If you have the necessary licenses and permissions, please try refreshing the page or logging out and logging back in to the Azure portal. If the issue persists, you can try using Azure PowerShell or Azure CLI to assign the Owner role. You can use New-AzRoleAssignment to assign the role. For example,
New-AzRoleAssignment -ObjectId $groupId ` -RoleDefinitionName "Owner" ` -ResourceGroupName "rbac-tutorial-resource-group"
Let me know if this helps and if you still run into this issue after trying these steps.
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