Have you updated your device recently?
You should go into the settings and make sure that app is exempt from any power optimization if you want to receive push notifications. The app needs to be running in the background for you to get push notifications but since that consumes power battery optomization will frequently prevent it. Also check which notification options are enabled for that app and what permissions the app has been granted. It could be the app is missing necessary permissions and that you will need to grant them manually for the app to function properly.
This is odd. If I'm on my members homescreen and click on the bell icon, it shows messages and notifications tab. I click notifications it shows my last notification is feb 24th. Obviously it's wrong since you all have been respond to this post recently.
Cleared cache. Recent notifications aren't showing up again on the tab. Last notifications listed on feb 24th. The other it listed new notifications but they aren't on there now.