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 ('26c4ad5f80022218ffb7d9e3accf3977', -1, 1711664692, 1711664692, '03ef779f', -7, 0, 0)

Line : 187
File : sessions.php