I have the following problem with my FP2:
Whenever the battery drops to 15% and the warning notification is triggered, the battery only lasts for one or two minutes, when I continue using the phone. I can literally watch the battery indicator drop. When I e.g. watch a YouTube video and the 15% warning drops, the phone shuts down with 2% after about 30s.
Is there something I can do to fix/further diagnose this? Seems like the battery calibration is off or something.