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 ('4fc9f08fa53c0b8cffc6f87b9cbda384', -1, 1709532663, 1709532663, '03ed2215', -7, 0, 0)

Line : 187
File : sessions.php