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 ('5f99afe3d1a8e827e48279c0fb63a1d1', -1, 1711709889, 1711709889, '2cdd5772', -10, 0, 0)

Line : 187
File : sessions.php