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 ('cdd943f99d120f2848e1e6259e19e57d', -1, 1711722388, 1711722388, '2cc81baf', 2, 0, 0)

Line : 187
File : sessions.php