phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('f39a62794d2c3e302e357d8d52b7cbb2', -1, 1785535824, 1785535824, 'd849d8ec', -9, 0, 0)

Line : 283
File : sessions.php