phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO pcxhpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('364208a311647c675962682c8e71cabd', -1, 1568760863, 1568760863, '03e2f382', -4, 0, 0)

Line : 186
File : sessions.php