one month back we bought Samsung S20. There is some bug when notification are disappering from lockscreen with your "Phone" app.
Android 11/OneUI 3.1 (SM-G980F/DS)
- uninstall all downloaded applications
- safe mode
- factory reset with full wipe
There are videos It is incoming call terminated by caller. Notification disappears from lockscreen. Now tested as anonymized (for hidding telephone number here). But it is doing with classic call too. It is only for test:
Without phone case:
With phone case:
Update system Google Play: 1.2.2021
Baseband version: G980FXXU6DUB5
Kernel version: 4.19.87-209392393#1 Thu Feb 25 17:41:31 KST 2021
Build number: RP1A.200720.012.G980FXXS6DUBA
Status SE for Android: Enforcing SEPF_SM_G980F_11_0008 Thu Feb 25 17:59:05 2021
Knox version: Knox 3.7, API level 33, TIMA 4.1.0, DualDAR 1.3.0, HDM 2.0 - 1F
Power Saving Mode disabled in Settings/Battery. And telephone is after factory reset - clean.
And they are ignoring it here. Please contact your support in your country. I did it. But classic response: we forward it on without any next info. 😐
Similar issue on Galaxy A51. After updating to Android 11 / One UI 3.0, notifications (missed call or message from WhatsApp) sometimes disappear from Always On Display and locked screen. It happens irregularly and randomly. The notification appears on the display for a second after a missed call (or message delivery) and then disappears. After unlocking the phone, the notification is on the notification bar.
Now I have to check the phone, I can't rely on the notifications on the display and it's annoying.