MX4 - Automatically kill processes

I have Meizu MX4 with Flyme version:
I noticed the device doesn’t allow to more than 2 or 3 applications to run in the background.
It’s mean that if I open certain application, minimize it and open 2 others applications, the first app reopened instead of maximized from the background.

I would like to note that I allowed my relevant apps to run in standby in the security app.
In addition, in the developer settings, the option ‘Do not keep activities’ is unchecked, and the option ‘Background process limit’ is setted to ‘Standard limit’.

Anyone can help me? It’s very annoying phenomenon.

Thanks a lot.

If you don’t want apps to be killed, try this. Open app, open taskbar by swiping up from bottom, tap and hold the app till the lock appears. Try again. Hope it helps.

BTW: use the search function next time, it could have helped you faster, since there are already some topics on this issue.

First of all, thank you for the help.
I have already tried this. The only thing it does is that if I open the taskbar and swipe down certain app (In purpose to kill all the running apps), the apps that I locked doesn’t being killed.
But the locked apps still killed automatically as I described.

I upgraded to 4.5.7I and it is still happen.

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