How do I get back my money?

I am an active duty member and have been paying CA state taxes when I shouldn’t been. I am currently stationed conus at a different state so I fall into the exemption for being a CA nonresident. My husband was also active duty and has paid CA state taxes for the past 5 years. How would we both get the money back for the years served as a CA nonresident — PCS’d with active orders and had CA as home of residence.