How and when to claim California AMT Credit?

Hi,

    In 2018, I have to pay CA AMT credit because I have exercised and held a lot of ISO.

    In 2019 last year, I have sold part of my ISO stock. From turbotax, I found Federal AMT credit has been used for Federal tax, but I did see my previous CA AMT credit has been used at all...

   Can someone tell me why, and how the AMT credit from California will be used? A FTB 3510 form should be filed when CA credit is claimed, right?

   I just do not want to lose my CA credit, or double pay the tax to CA.

 

Thanks,

Rick