If your appliance isn't working, and you suspect it's because of the GFCI outlet, try unplugging all appliances and resetting the GFCI. If it resets, plug in appliances one at a time until it trips again to identify the culprit. Check for any other outlets or devices connected to the GFCI's LOAD terminals that may be causing the issue. If the issue persists, it may be a hard-wired load or wiring issue, and you should call a trained electrician to perform more advanced troubleshooting.