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 ('a256cc345b4c50730ce1d2e02dbaf198', -1, 1711712372, 1711712372, '03e57b50', -1, 0, 0)

Line : 187
File : sessions.php