My own take on this is that there's more to the story. And in any case, the Internet is a lousy place for the OP to come for advice on a real life legal matter.
 No one can really help without all the information. There may be details that are important but are missing. At this point we have only the sketchiest of information.
 The Internet is a public place. What's discussed here is NOT confidential. It's a bad idea to discuss personal, serious matters with strangers in public.
 The OP needs to find out what appeal mechanism is available and pursue that.
 The best thing would be for the OP to find a qualified gun rights lawyer. Among other things, what the OP and his lawyer discusses is confidential.
 Some good gun rights lawyers in California are:
DAVIS AND ASSOCIATES
30021 Tomas Street, Suite 300
Rancho Santa Margarita, CA 92688
The Law Office of David J. Salvin
A Professional Corporation
23276 South Pointe Dr., Ste 216
Laguna Hills, CA 92653
Tel: (949) 305-6400
Michel and Associates
180 East Ocean Boulevard #200,
Long Beach, CA
Direct: (562) 216-4441
Assistant: (562) 216-4458
The California Gun Attorney
PO Box 10787
San Bernardino, CA 92423-0787
800-560-8000 toll free
Now I'm going to close this thread because with the minimal information we have anything further will be speculation.