My California refund was almost 600 dollars less

California should send you a notice within a couple of weeks explaining why they reduced your refund. No one at TurboTax or on this site has any access to refund information. You could contact the state to try to get answers. Here is a link with state contact information: https://ttlc.intuit.com/questions/1899433-how-do-i-track-my-state-refund