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 ('8757960248b628e5e9fc9a96d9385cdd', -1, 1757348881, 1757348881, 'd849d8bb', -9, 0, 0)

Line : 187
File : sessions.php