The answer to 'GFCI outlet not working' is that a GFCI (ground fault circuit interrupter) outlet may not be working due to a variety of common causes, including tripped breakers, loose wiring, or a faulty GFCI device. Symptoms of a non-working GFCI outlet include the inability to reset the outlet, no power to connected devices, or the GFCI constantly tripping.
To troubleshoot a GFCI outlet, first check the circuit breaker to ensure it has not tripped. If the breaker is fine, use a GFCI tester to check if the outlet is functioning properly. If the GFCI is faulty, it will need to be replaced. For more complex issues like loose wiring or a problem with the electrical system, it's best to call a licensed electrician to diagnose and repair the issue.