phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO cristianismo_phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('aa89530e0fd394f81b1803d1172c3f14', -1, 1216908973, 1216908973, '26673f11', 0, 0, 0)

Line : 187
File : sessions.php