Why do I not always receive Facebook Messenger notifications

[Emily60]

I have a Huawei P30 Pro. I have an issue with my phone that I can't resolve. I do not always get Messenger notifications, sometimes they come through, sometimes they don't. It seems to be that when I haven't used Messenger for a while, they don't come through. When I open the app, they will come through, or sometimes when I'm in Facebook I can see from there that I have a message. But otherwise they just sit there unnotified. The person who has sent them can see it hasn't delivered and it is unread. It doesn't always happen, sometimes they come straight through like they should.
I've googled this issue and tried everything that has been suggested... restarting my phone, clearing the cache on Messenger. I've gone into settings for the app, data settings, battery settings, settings for Facebook, I cannot see anywhere that I am blocking notifications. I am allowing it to work in the background, I haven't turned on any battery performance settings. I get notifications for all my other apps.
Can anyone suggest anything that I might have missed or could try?

 

[B. Diddy]

Welcome to Android Central! It might be due to the firmware killing apps too aggressively in the background in a misguided attempt to save battery. Chinese manufacturers tend to do this a lot: https://dontkillmyapp.com/. As an example, I found that I couldn't listen to Spotify in the background on my TCL Tab 8 -- soon after I switched to another app, Spotify would be killed in the background, which is ridiculous behavior for a music app. But there wasn't anything I could do about it.

Please register on this forum, which will allow you to engage in discussion more easily, as well as post images. https://forums.androidcentral.com/ask-question/409154-join-android-central-community.html

 

[Emily60]

Thanks for your reply. I've now registered, this was my question. I'll have a read of the link you've shared.

 

[B. Diddy]

Ok, I made you the owner for the original guest post to make it easier for you to find.