You can set on the Huawei P20 Pro what the app indicator should display on the home screen. This can be used either for new messages or for notifications in general.
Depending on what you prefer, you will need to set the appropriate setting on the Huawei P20 Pro. Where and how to change this setting for the App Indicator is explained in this article:
1. Return to the Huawei P20 Pro home screen
2. Press and hold a finger on a free space (No Widget or App)
3. A menu will appear in which you now navigate to "Settings" at the bottom right
4. Here you will find the option: App News icon
5. Select the option and a list of all possible apps will open
6. Tap on "Emblem display mode" at the top. A radio button opens with:
- Notifications Unread messages
7. Select your preferred setting for the App Indicator
Here, the indicator is then used for the Apps either for unread messages or for any type of notification.