The phrase numéro non attribué is the standard French wording used by telephone networks when a dialled number has not been allocated to any subscriber. Unlike a busy signal, it explains in words why the call cannot connect, which made the recording easy to reuse outside real calls. Clips of the message spread on French soundboards and in prank videos, where creators use it as a fake response from a phone company. Its polite, administrative tone is why it still works as a joke about being ignored, blocked or impossible to contact.