NEW YORK (AP) — Shares of Twitter are down more than 9% in the first day of trading after billionaire Elon Musk said that he was abandoning his $44 billion bid for the company. The social media platform vowed to challenge Musk in court. Musk alleged Friday that Twitter has failed to provide enough information about the number of fake accounts it has. Twitter has said for years in regulatory filings that it believes about 5% of the accounts on the platform are fake. Twitter shares fell below $34 in early trading, far below the $54.20 that Musk agreed to pay, suggesting few investors believe the deal will go through.