Problem with flying superpower

 One of the most popular super-power is flying (like Superman).
I'm a bit scared of this superpower. I like it, but I'm scared
If while flying this superpower deactivates? And you will not be notified before somehow. You're gonna fall and die. Or if there's some kind of notify service (VIA SMS or with Elon's brain chip) and you don't have time to land safely from the moment you've been notified.
 
A way to convince me to have this superpower is to have a scientific or semi-scientific explanation for when I run out of flying energy or something. Or have a backup flying superpower in case of failure.