How can I rectify my registration citation in Santa Monica?

I’ve been trying to call the courthouse for the last 3 weeks, but they just drop the call if there’s anyone waiting on the line. I know it’s a simple fix it, but I’m wondering 1) What I need to show and 2) Where I could mail the information and 3) How much to pay.

I’ve tried googling, and I really can’t find anything. Help!