My child welfare worker lied about my babies toxicology report and then my baby was apprehended. what can i do?

my baby was apprehended 12 hours after birth. a social worker came in n asked a couple questions, n left returned later n took her, beacause of my past with child welfare n my past drug abuse problems they did a toxicology report n said if babhy was clean she could come home. th worker said it was positive for drugs and i knew it was wrong, i got it back n was proven baby was clean. how can i get my baby back.