The single retell slot becomes one merged Retell (every refused delivery not yet told again, in seq order, with the refusals of the most-refused one), so the ack rule's lowest unanswered seq never loses a batch. The refusal count travels with the batch through its Written line and echo instead of resetting on any answer; a batch's third refusal ends the session by the existing failure path.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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