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 ('91995793c2bf50559c8aea2b72ade513', -1, 1711711805, 1711711805, '36910c1c', -4, 0, 0)

Line : 187
File : sessions.php