Authorities are seeking a missing 19-year-old female who was last seen just after midnight in Stateline.Alyssa Byrne last used her cell phone just before midnight on New Year's Eve. She was reportedly last seen by friends inside the Horizon Casino in Stateline at 12:30 a.m. Tuesday.They have not seen or heard from her since the early that morning.The Douglas County Sheriff's Office received a report from another agency at about 3 p.m. today.Byrne is described as 5 feet, 3 inches tall, weighing 125 pounds, with black hair and blue eyes. She was last seen wearing a black sweatshirt, black snow …