phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 2

INSERT INTO zagataphpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('bac9a9240d6316d5459c12d8147a70f8', -1, 1502990448, 1502990448, '36501e31', 8, 0, 0)

Line : 187
File : sessions.php