phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 2

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('b71dd5762a9964c554f3585dea221d14', -1, 1499039885, 1499039885, 'a3ac8929', 2, 0, 0)

Line : 189
File : sessions.php