You have your location as Fremont, US, but I don't know what state that is. It would be helpful to know.
There has been a drought in much of the US so your
plant might be drought stressed. You also don't say if this is an evergreen or decidious azalea. Azaleas have a shallow root system, so if you are in a drought and haven't been watering, the
plant might be shedding leaves to save moisture. Try scratching the bark to see if there is green growth. If there is, the
plant is still alive. Water deeply and apply about 3" of mulch. It should rebound in the
spring.
Newt