INS 8.2 Understand the three supplied roles

The interface names them Utilisateur, Speech Admin and Admin.

Rôle	Described as	Autorisations held	Delete offered
Utilisateur	"Standard tenant user."	9, beginning View Request Metadata and View Appel Aperçu	Yes
Speech Admin	"Universal administrator."	76, beginning Create Telcos and View Telcos	No
Admin	"Locataire administrator."	46, beginning Create Locataires and View Locataires	No

Speech Admin is by far the broadest, and it reaches above your tenant. It holds 76 permissions against Admin's 46 and Utilisateur's 9, and the first two are Create Telcos and View Telcos. A Telco sits above a tenant in the platform hierarchy: a Telecom is assigned the platform and then creates tenants beneath it. So this role's scope extends past your own organisation. Assign Speech Admin only where that is genuinely intended, and confirm with support@ncsapp.com exactly what it reaches outside your tenant before granting it to anyone.

The gap between the roles is very wide. There is nothing between a 9-permission Utilisateur and a 46-permission Admin. If you need a supervisor who can read call content but not administer the tenant, build a custom role (INS 8.3) rather than reaching for Admin.

Delete is not offered on every role. It is offered on Utilisateur but not on Speech Admin or Admin, so the two administrative roles cannot be removed from this page. That is a deliberate protection, not a permissions problem with your account.