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 ('53b76cbe34abb80c8e8694e3c19b3c11', -1, 1563409274, 1563409274, '365c94a5', -4, 0, 0)

Line : 187
File : sessions.php