Kaspersky Who Calls may have the following issues (and solutions) on Meizu devices:
Kaspersky Who Calls may not work correctly when the device is in the sleep mode. To fix this, go to Settings > Device > Power Management > Energy consumption > Optimization of energy consumption > Sleep mode management and allow Kaspersky Who Calls to keep working in sleep mode.
Some steps may be different depending on the device model and version of the operating system.
Kaspersky Who Calls may not display caller ID info in the pop-up notification. To fix this, in the device's Security Center, allow Kaspersky Who Calls to display notifications.
Kaspersky Who Calls may not start after the device is restarted or the app is unloaded from memory. To fix this, grant Kaspersky Who Calls permission to autorestart.
Kaspersky Who Calls may be unloaded from device memory. For the app to work correctly, lock the app in memory.
For example: on Meizu M5 Note Flyme 6, go to Security > Permissions > Run in background > Kaspersky Who Calls > Allow running in background.
Some steps may be different depending on the device model and version of the operating system.
MEIZU M2 MINI:
Caller ID info in the pop-up notification may not be displayed on the Meizu M2 Mini with Flyme 5.
MEIZU PRO 6 PLUS:
Kaspersky Who Calls may not get access to permissions on Meizu Pro 6 Plus with Android 6.0.1, in which case the app will not work properly. To fix this issue, please upgrade to Android 7.x. Otherwise, do the following:
Go to Settings > Apps > Who Calls > Permission management.
Grant all permissions: set permissions to ON or tap a permission name and select Allow from the list.