Sometimes App Store Server Notifications do not reach our endpoint

Hello

We have App Store Server Notifications v2 enabled for our app (we're selling renewable subscriptions), but recently some notifications of type SUBSCRIBED:INITIAL BUY have been missing (not reaching our endpoint).

However, we get DID_CHANGE_RENEWAL_STATUS notifications for these users later and we get SUBSCRIBED notifications for other users, currently this thing looks pretty random.

We've had several cases in the last few days. Example originalTransactionId: 110001866285315. We'd appreciate if Apple engineers could check it, or maybe anyone could share a similar experience. Thanks!