My employer deducted MD withholding since my old address and employer are from MD but my job is in CA and i lived here for the whole year (almost), what should i do now??

I have old Maryland Address on my W2 but all my other documents have my updated CA address and everything since i lived here for whole year. I moved here for a new job as a contractor but my employer is from MD and deducted MD withholding and address on w2 is from MD as well. What should i do now? please help