number.confirm

Confirm a caller-owned pending reservation after both reserved numbers join the group. This operation atomically associates the reservation with the group and makes the reserved primary active. Membership events do not associate reservations. Another live reservation already linked to the group is rejected; a confirmed reservation can only replay its original group. Before confirmation, membership and pending reservation may conservatively both count toward occupancy.

POST /internal/messaging/v1/numbers/reservations/{reservation_id}/confirm