There's nothing a FA can do for an individual power outlet. There's circuit breakers, but it's not at the individual seat level. Basically they can turn them all off/all on. They can't just do your seat.

To get fixed, must send write up to maintenance. Getting maintenance out to fix one broken outlet isn't practical. For short domestic turns anyway. If this was a say D1 seat on A330 going international then it's more worthy. (Also I believe there's normally maintenance at plane for long haul international departures)