One of my W-2 forms has my full income duplicated in box 16 for my state of residence (CA) and for my state of employment (NY), how do I claim my resident state income tax that has been withheld?

I have lived in NY all last year. Unfortunately, on my W-2 my residence address is California. I have reached out to my employer to correct my W-2 but they are not willing to correct. How do I go about filing my state returns? I thought about not filing for CA but that means I can't claim the CA state income tax that has been withheld.  Looking for direction. Thank you.