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 ('ac764ccd02831d2471ff6e0248f4db14', -1, 1711639931, 1711639931, '03ef779f', -8, 0, 0)

Line : 187
File : sessions.php