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 ('b1011c4edc0ce9da8c0c499da70db2f4', -1, 1711666879, 1711666879, '12e8bc7a', -4, 0, 0)

Line : 187
File : sessions.php