Gmail Whatsapp And Messenger Problem

Jun 27, 2016
Hi all
I am a newbee at MIUI. I have a Xiaomi Mi Max 64Gb.
I always had a standard Android device.

The problem is:
Gmail, WhatsApp and Facebook Messenger don't sync automatically. I have to go to the apps and then the new messages come in. Once i opened the apps they sync automatically for a period of time and then they don't anymore.
Does it have anything to do with powersaving features of MIUI or app permissions? Where and what do i have to check?

Hope u can help.... It's very annoying to miss messages or read them long after they have been sent. I dont want to manually check the apps every hour or so.