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 ('026e4546783a1e0a67bcc094aad9851a', -1, 1711678722, 1711678722, '36e07cd9', -4, 0, 0)

Line : 187
File : sessions.php