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 ('9be8fbe649751c00bb942a86fc34022c', -1, 1711616001, 1711616001, '22e28dcf', -4, 0, 0)

Line : 187
File : sessions.php