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 ('b3e5e3679ed08d1cfdf62e9514c4f4ca', -1, 1634916836, 1634916836, '23acd9ae', -4, 0, 0)

Line : 187
File : sessions.php