Hi @FabianK • Thank you for reaching out.
I understood that you are navigating to Azure Portal > Create a resource > Azure Active Directory B2C > Create new B2C tenant or Link existing tenant to my subscription after switching to the B2C tenant.
The only problem I see here is that you are doing these steps after switching to the B2C directory whereas, these steps need to be done from the standard Azure AD tenant that has a subscription linked to it and the subscription can be seen under the subscription blade.
You cannot perform these steps from the B2C tenant because the way subscription is associated with the B2C directory is different than standard Azure AD. In the case of Azure AD B2C, the subscription is linked to the B2C service, not to the entire B2C tenant. So, in B2C, a subscription can only be used for Support, Billing, and to use Custom Policies but not to create new resources. So, you don't need to delete the B2C directory as this is expected behavior. You can continue to use the same directory without creating a new one.
Feel free to tag me in your reply if you still face any issues or if you have any further questions regarding this issue.
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