Does it say unknown ? Or from another player
If you click start & go to info tab you will see the previous notifications
Also if you logout or move to another session the bounty is still in effect
And if you steal a nice car from a person not human they can put a bounty on you , it will say unknown put a bounty on you
After a while of playing in the same session if nobody kills you the bounty money is yours , but this only works if you stay in the session long enough not moving from session to session I think
After you reach a certain lvl bounties will be placed on you for certain actions be NPC's. I jacked someone's car in a solo session & they sent me a text saying I jacked their ride and they was gonna get payback. I got that message for like two real world days. If you play for a GTA world day without getting killed you get a achivement for it.
This makes sense. I get a lot of text from unknown


Sent from my Galaxy S4