phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO forum_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('80c859c832ba2aebd38e4cae37c9aa90', -1, 1539696229, 1539696229, '36e076f7', -2, 0, 0)

Line : 187
File : sessions.php