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 ('9642c31850a4a57e2a44fe0d3f367047', -1, 1713959897, 1713959897, '031042ce', -4, 0, 0)

Line : 187
File : sessions.php