IHSS Income Taxes Withheld

For 2019, I had IHSS income since I was a provider for my mother (Recipient). My mom lives in the same house as me. I didn’t realize that the IHSS income should have been exempt for federal and state taxes. However, I did pay federal and state taxes in 2019 for the IHSS income. I have received the W2 form which shows the taxes withheld.

 

I did call the county IHSS and they offered to fix it for year 2020. They said they can’t do anything for 2019 year.  Question:

 

How do I get the federal and States taxes back from the 2019 year (which should have been exempted).