Wake
Apple sees timing and a device token. The delivery server stores that token next to a mailbox. Neither one gets the message, the sender, or an amount.
How to
SILNT notifications.
The server cannot write a preview. The push that wakes the phone carries no content and no sender.
Banner
Previews default off. The banner reads only New message. Turn them on in Settings if you want a sender and a line of text. Decryption happens on the device, after unlock.
Lockdown
Lockdown forces previews off. You cannot turn them back on while it is enabled.
iOS settings
If nothing arrives, check iOS Settings, Notifications, SILNT, then reopen the app. The delivery server still cannot fill in a preview you have not decrypted locally.
In the app: Settings, How to, Notifications.
