A friend on PC/Steam experienced this.
After getting the tracker from the first Firebird, he exited without progressing any further.
The next time he logged in, the mission had disappeared from the quest log, and Firebirds didn’t drop any more trackers. So now he can’t complete the mission.
Possible fixes:
- Make sure the mission doesn’t disappear just after it had started.
- Make firebirds drop additional trackers, so that mission can be picked up again.
There is a similar report on Reddit.