1.Make sure that your phone is connected to the network.
2.Go to [Settings] >[Notification and Status bar] >[Manage notifications], click the application and enable [Allow Notifications].
3.Make sure that [Low Power mode], [Airplane mode], and [Quiet Time] or [No disturb mode] is turned off.
4.Click the menu button and slide down the application page until you can a lock icon in the upper corner to allow applications to run in the background.
5.Go to [Phone Manager] or [Security Center] or [Security] > [Privacy Permissions] > [Startup Manager] and turn on the button to allow the application to start on boot and start in the background.
6.Check if there are any updates of the application and download the latest version in [Play Store].
7.Update the system to the latest version.
Source: Realme