When the webhook gets deactivated after 72 hours due to webhook receiver fails to respond, is it possible to get the notification from Adobe Sign?
No, if the Webhook receiver fails to respond within 72 hours, the webhook gets disabled and no notification is sent to customer from Adobe Sign.
https://helpx.adobe.com/in/sign/help/adobesign_api_webhooks.html
If the target URL for the webhook is down for any reason, Adobe Sign queue up the JSON and retry the push in a progressive cycle over 72 hours.
The undelivered events get persisted in a retry queue and a best effort is made over the next 72 hours to deliver the notifications in the order they occurred.
The strategy for retrying delivery of notifications is a doubling of time between attempts, starting with a 1-minute interval increasing to every 12 hours, resulting in 15 retries in the space of 72 hours.