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 ('730e74ba19e1e2956c76951fe0a830ec', -1, 1711718484, 1711718484, '2cc93b14', 0, 0, 0)

Line : 187
File : sessions.php