Server-to-server notification received 2 days after subscription

One of our customers subscribed to a monthly plan on August 16 but the server-to-server notification seems to have been sent on August 18.

What could be the reasons for such a delay between the purchase and the server-to-server notification which are usually sent right after the purchase?

The receipt sent along with the notification seems to confirm that the receipt has only been created 2 days after the purchase. Here is an extract:

{
  "environment": "Production",
  "receipt": {
    "receipt_type": "Production",
    "bundle_id": "fr.gaumontvideo.gaumontclassique",
    "application_version": "613",
    "receipt_creation_date": "2025-08-18 13:00:16 Etc/GMT",
    "receipt_creation_date_ms": "1755522016000",
    "receipt_creation_date_pst": "2025-08-18 06:00:16 America/Los_Angeles",
    "request_date": "2025-08-25 13:08:27 Etc/GMT",
    "request_date_ms": "1756127307346",
    "request_date_pst": "2025-08-25 06:08:27 America/Los_Angeles",
    "original_purchase_date": "2022-05-11 06:14:37 Etc/GMT",
    "original_purchase_date_ms": "1652249677000",
    "original_purchase_date_pst": "2022-05-10 23:14:37 America/Los_Angeles",
    "original_application_version": "265",
    "in_app": [
      {
        "quantity": "1",
        "product_id": "fr.gaumontvideo.gaumontclassique.subscription.monthly.apple",
        "transaction_id": "270002386706194",
        "original_transaction_id": "270002386706194",
        "purchase_date": "2025-08-16 08:02:06 Etc/GMT",
        "purchase_date_ms": "1755331326000",
        "purchase_date_pst": "2025-08-16 01:02:06 America/Los_Angeles",
        "original_purchase_date": "2025-08-16 08:02:08 Etc/GMT",
        "original_purchase_date_ms": "1755331328000",
        "original_purchase_date_pst": "2025-08-16 01:02:08 America/Los_Angeles",
        "expires_date": "2025-09-16 08:02:06 Etc/GMT",
        "expires_date_ms": "1758009726000",
        "expires_date_pst": "2025-09-16 01:02:06 America/Los_Angeles"
  }
}
Server-to-server notification received 2 days after subscription
 
 
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