Actually I am also facing the problem with P8 Max. I got two version, one is china version and the other is international version. Both same problem. The only other way is to run the application on the background, then all message come in will have immediate notification. If you kill the apps, you will only get those message when the start the app.

I have read xda and all other forum, apparently the culprit is Huawei phone manager app which have too tight security. Many said that the problem will be solved once you remove this app. As this is default app, the only way to remove it is to root your phone which I am not ready to do that yet. I am currently leaving the apps running on background and so far so good.

Strange is that this did not happen when i previously use Mediapad X1 and Mate 7 running kitkat. Only recently when update to lollipop, this happen. Even my other G7 also have no such issue but running kitkat.

Update: There seem to be update for Whatapp and it seem that its fixed for my international version of P8 max. It is now working even when the apps is not running at background . But the China version is still facing the same problem

I recently got Mediapad M2 and I have just tested, No issue for this as well running lollipop.

This post has been edited by pwf: Jan 22 2016, 10:42 AM