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 ('844de1178be12c0321c9c36eefd9f63f', -1, 1711709906, 1711709906, '22ef96f7', -4, 0, 0)

Line : 187
File : sessions.php