After exchanging messages with Apple team, the issue is resolved now and we don't see any occurrence of this error.
seinshah_t
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As another reference, there is a documentation in version 1 of server notification https://developer.apple.com/documentation/appstorereceipts/is_in_billing_retry_period:
Implement a grace period to improve recovery, if the value is “1” and the expires_date is in the past. A grace period is free or limited subscription access while a subscriber is in a billing retry state.