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 ('cffc5a12ae4e5eb566f00e0bb3227755', -1, 1560854287, 1560854287, '035482fc', 27, 0, 0)

Line : 191
File : sessions.php