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 ('049d704e60e845714437b68f00e0132e', -1, 1711708865, 1711708865, '22eef2a8', -4, 0, 0)

Line : 187
File : sessions.php