How To Log Out Of Facebook Messenger On Android ?
On your Android phone launch settings and go to Apps On some devices you have to go to more and then applications manager
Now on Apps swipe to Downloaded tab and find messenger .
open Messenger it will show you Appinfo click on Clear data a dialog box appears with confirmation click on Ok.
Now the “Clear data” button becomes grayed outs to 0.00B. And you will be logged out of your Messenger app.