phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('97fa60f0fe5b3d9425020ad01366223c', -1, 1540044441, 1540044441, '36e09618', 0, 0, 0)

Line : 187
File : sessions.php