Richardson was last seen in the early morning of September 17, when she was released from the Lost Hills Sheriff's station in Malibu Canyon.
She had been booked the previous night after reportedly acting strangely and walking out of a Malibu restaurant without allegedly paying her bill.
There has been no activity on her bank account or credit cards since then, and police tell Eyewitness News there is no evidence of foul play.
Richardson is described as black, 5 feet 5 inches, about 135 pounds, with brown, curly hair and hazel eyes. She has tattoos on her lower abdomen and behind her neck.
She was last seen wearing a dark shirt and blue jeans.
Anyone with information is asked to call detectives at (213) 485-2531.