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providers.callback_rejectedprovidersRule R15The callback failed verification
An incoming provider callback was refused: a bad signature, a timestamp outside callback_timestamp_window_seconds, or a source address off the provider's allow-list. CallbackRejected is emitted and no payment changes — that is the whole point of the rule.
Why the API refuses
WHEN a received callback fails the adapter's signature check, arrives outside callback_timestamp_window_seconds or comes from an address outside the provider's callback allow-list, THE SYSTEM SHALL reject it with the matching reason, emit CallbackRejected and answer providers.callback_rejected without changing any payment.
What to do
Rejected callbacks are visible to operators at GET /callbacks?status=rejected with the reason. If you are the one sending callbacks (a sandbox or a custom adapter), check clock skew first — a machine minutes out of step fails the timestamp window while the signature is perfectly valid.