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 ('4d754ad5f86f70fa2b059aaa4612f6fc', -1, 1711710384, 1711710384, '22cf89f5', -4, 0, 0)

Line : 187
File : sessions.php