Hello @Samy LEROI ,
Thanks for reaching out.
You must have Azure AD administrative roles to manage Azure AD B2C Tenant (such as Global administrator or one or more of the limited administrator roles in directory, more information refer ) because Azure RBAC roles (Ex: Owner, Contributor and Reader etc.., ) are different from Azure AD roles (Ex: Global Administrator, User Administrator and Directory Reader etc.., ).
The following diagram is a high-level view of how the Azure roles and Azure AD roles are related.
To manage Azure resources in given subscription, the user must have any of these Azure roles and for AAD/B2C directory then any of these Azure AD roles to manage the directory
To know more about, refer How the roles are related .
Hope this helps.
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