Exclamation bottom navigation bar disappear when receiving a call

Hello everyone, few days now I have an issue with my nexus 5. Before i start im on a stock rom 4.4.4, rooted with xposed installed.
So when I'm receiving a call during an open application like facebook (or any other) the bottom navigation bar disappears, the scroll down option of the notification bar is not working and it doesn't show me the call answer screen. The only thing that i can do is just to lock the device but it doesn't fix it , or continue browsing the open app. Also it shows me only an icon of the phone on the notification bar. Does anyone else had this issue? If yes how i can fix it? thank you